Elon Musk has accused Mark Zuckerberg of failing to understand artificial intelligence.

It comes after the Facebook boss said that the doomsday scenario put forward by Mr Musk was unhelpful.
Mr Musk tweeted: "I've talked to Mark about this. His understanding of the subject is limited."
The pair represent two distinct groups, those saying AI's benefits will outweigh its negatives and those saying it could ultimately destroy humanity.
Mr Zuckerberg's comments were made as part of an informal Facebook Live chat, aired during a barbecue at his Palo Alto home.
A viewer asked him about a recent interview with Mr Musk, in which he said his biggest fear for the future was AI.
"I have pretty strong opinions on this. I am optimistic. I think you can build things and the world gets better. But with AI especially, I am really optimistic," Mr Zuckerberg replied.
"And I think people who are naysayers and try to drum up these doomsday scenarios - I just, I don't understand it.
"It's really negative, and in some ways I actually think it is pretty irresponsible."
"In the next five to 10 years, AI is going to deliver so many improvements in the quality of our lives."
Mr Musk began warning AI could destroy humans three years ago, when, during a talk at the Massachusetts Institute of Technology, the billionaire Space X founder called it humanity's "biggest existential threat".
And he has founded OpenAI, a billion-dollar non-profit company working for "safer artificial intelligence".
Bill Gates has also voiced concern about the threat AI poses, as has Prof Stephen Hawking.
But Mr Zuckerberg said: "AI is going to make our lives better."
And Facebook, the company he founded, uses AI to offer better targeted advertising, for curating news feeds and for photo tagging.


Cycling continues to struggle with widespread doping, according to a landmark report into the sport's troubled recent history.

Set up last January to investigate how cycling so badly lost its way during the 1990s and 2000s, the Cycling Independent Reform Commission (Circ) has heavily criticised the sport's leadership throughout that era.
Its 227-page report, published on Monday, clears the International Cycling Union's (UCI) bosses of outright corruption but censures them for a litany of failings.
Foremost among these are that the UCI did not really want to catch cheats and therefore turned a blind eye to anything but the worst excesses.
The report's authors also accuse former UCI presidents Hein Verbruggen and Pat McQuaid of failing to follow their own anti-doping rules and showing preferential treatment to disgraced former champion Lance Armstrong.
A total of 174 anti-doping experts, officials, riders and other interested parties were interviewed. These are the main points:
The €3m (£2.16m) report was compiled by chairman Dr Dick Marty, a former Swiss prosecutor, and two vice-chairs, German anti-doping expert Professor Ulrich Haas and Peter Nicholson, an Australian who has investigated international terrorism and war crimes.
UCI president Brian Cookson, who swept into office in 2013 promising a fresh start for an organisation that had been badly damaged by its close links to Armstrong, thanked the panel for its work and did not try to sugar-coat its findings.
"It is clear that in the past the UCI suffered severely from a lack of good governance with individuals taking crucial decisions alone," said Cookson.
"Many [of these decisions] undermined anti-doping efforts; put the UCI in an extraordinary position of proximity to certain riders; and wasted a lot of its time and resources in open conflict with organisations such as the World Anti-Doping Agency (Wada) and US Anti-Doping Agency (Usada)."
Cookson added that his predecessors and their close associates regularly interfered in anti-doping cases which "served to erode confidence in the UCI and the sport".
The issues that Cookson is referring to are dealt with over 120 pages of forensic detail.
The report explains how a sport that had always taken a lenient approach to doping, and had an entrenched, Mafia-like culture of "omerta" when it came to not talking about doping, entered a new phase when the "game-changing" blood-boosting drug EPO became readily available in the early 1990s.
With no test for it until 2000 and performance benefits of 10-15%, it did not take long before almost everybody in the sport was using it. As the report says, "it would have been hard to overestimate the prevalence of drug use in the peloton" at this time.
Numerous interviewees told Circ the UCI's view was it should only try to contain the problem and make sure the riders did not kill themselves, and that actually catching cheats was bad for the sport's reputation.
It was against this backdrop that Verbruggen took control of what had been an insignificant governing body and turned it into a far larger and more ambitious entity.
According to the report, the Dutchman had almost dictatorial powers at the UCI between 1991 and 2005, and continued to exert influence under the reign of his hand-picked successor, Irishman McQuaid.
The pair will be relieved to have been cleared of the most serious allegations against them, namely that they were bribed by Armstrong to cover up positive tests in 2001; and that he paid for what was meant to be an independent report commissioned by the UCI to investigate reports he had tested positive during the 1999 Tour de France.
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But Circ did not spare them on a number of glaring errors of judgement and examples of poor governance:
There is also considerable criticism of the UCI's cost controls, ethics procedures and electoral practices, with Verbruggen and McQuaid accused of breaches of the rules in the 2005 and 2013 elections.
Both men have reacted by welcoming the report's central finding that there is no evidence of corruption or direct collusion in any of the numerous doping scandals that beset the sport on their watch, with Verbruggen telling the BBC: "How can I be annoyed about being cleared of cover-ups and bribes?"
He added that it is "so easy to rewrite history 25 years later".
One man who would dearly love to rewrite history is Armstrong, who told the BBC last month he hoped his two interviews with Circ would lead to the panel recommending a reduction in his lifetime ban from almost all organised sport.
The former icon will be bitterly disappointed, then, that Circ has not exercised its right to ask Usada to reconsider its sanction, despite noting on more than one occasion that his treatment is inconsistent with almost every other member of his team, not to mention the vast majority of riders he competed against.
Armstrong told the BBC he was "grateful" to Circ for letting him help with the report and said he was "deeply sorry for many things I have done".
While many senior figures within the sport will be feeling very bruised by the report's assessment of what happened during the EPO era, Circ did acknowledge the huge improvements made in the anti-doping effort, particularly after 2006.
It noted a far more aggressive approach to catching cheats, greater investment in anti-doping and the early adoption of the biological passport, the most effective tool in the fight against cheats since the EPO test was introduced in 2000.
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But the interviewees also made it clear that doping had not been eradicated.
The report listed dozens of substances and cutting-edge doping methods that riders are still believed to use. It also noted that teams do not know where their riders are training at all times, or with whom they are training.
The ready availability and falling costs of doping products is also flagged up as a huge concern, as is the continuing involvement of a number of unethical doctors.
The report concludes with a raft of recommendations to help prevent cycling from ever returning to the dark days of a decade ago, with ideas such as centralised pharmacies at races, a powerful riders' union, a greater push to encourage whistleblowing and more testing done overnight to catch micro-dosers.


Republic of Ireland will have to perform as well as they did to beat Italy at Euro 2016 when they face Wales in a World Cup qualifier on Friday, says manager Martin O'Neill.

Robbie Brady's 85th-minute header put the Republic into the last 16 of Euro 2016 as they beat the Azzurri 1-0.
O'Neill's side top their World Cup qualifying group, with Wales third.
"There is a distance to go. By the time the game is done we're halfway through the campaign," O'Neill said.
Referring to the Italy game, he added: "It's not a distant memory. Some of the players who performed that evening can call upon the experience again and go for it.
"I think we will have to produce a performance like that against Wales. I think the players are ready for it."
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The Republic drew against Serbia in the opening game of their qualifying campaign but have since beaten Georgia, Moldova and Austria.
"We've got 10 points on the board and three games away from home but naturally we are going into the Wales game with confidence," O'Neill added.
"Teams are capable of taking points off each other and that's been proved."
Despite being without Daryl Murphy, Shane Duffy, Wes Hoolahan, Ciaran Clark, Harry Arter and Robbie Brady, O'Neill believes he has enough depth to cope.
"We've lost a couple of big players but we have players who can come in and who want to play. Regardless of what league they're in, they want to play as strongly as possible if they want to get in the team," he said.
"I think us qualifying for the Euros and our achievements out there at the time means the younger players want to be part of it, not just in the squad, but in the team."


A row has broken out over the sale of a dinosaur skeleton at auction in the US.

The rare Tyrannosaurus bataar, 7m long (23ft), was bought by an anonymous bidder for more than $1m (Â£630,000) in New York.
The sale went ahead despite protests from the Mongolian president.
Elbegdorj Tsakhia says the skeleton, unearthed in the Gobi Desert, came from Mongolia and that exporting fossils found in the country is illegal.
The auctioneers, Heritage Auctions, say the specimen was imported legally. A restraining court order in the name of the Mongolian leader was put on the sale.
Tyrannosaurus bataar is an Asian cousin of the meat-eating Tyrannosaurus rex.
The skeleton in New York is thought to be one of the most complete and well preserved ever discovered, says the BBC's Jonathan Blake in Washington.
"When it comes to dinosaurs, number one, dinosaurs in general are extremely rare. But the rarest of the dinosaurs are the carnivores, the meat eaters - the top of the food chain if you will," David Herskowitz, director of natural history at Heritage Auctions, told APTV.
"And, of all the meat eaters that are out there, the most famous are the Tyrannosaurids. They are the most desirable, but they are the most elusive. They are the most difficult to find. Even though they are so big, there are not that many of them around."
Found about seven years ago in the Gobi Desert, the T. bataar remained in storage in England.
The T. bataar was slightly smaller and had longer arms than its cousin, Mr Herskowitz said.
This is the second Tyrannosaurid to be sold at auction, says Mr Herskowitz. The first was a T. rex named Sue sold in 1997 for more than $8m.
Lawyers for the auction house say the sale did not break any US laws - but it will not be confirmed until it has been approved by a US court.


Mass killings by Islamic State militants have seen 322 members of an Iraqi Sunni tribe killed in western Anbar province, Iraq's government says.

The country's ministry of human rights said more than 50 bodies were found in a water well, whilst 65 members of the Al-Bu Nimr tribe have been kidnapped.
The group's latest attack came on Sunday morning when militants shot and killed at least 50 of the tribe.
IS militants - also Sunnis - control large areas of Iraq and Syria.
The ministry said IS is holding the 65 hostages as prisoners of war. The jihadist group also stole livestock from the tribe, it said.
A senior leader of the tribe, Sheikh Naeem Al Gaoud told the BBC: "The government abandoned us and gave us to Isis on a platter.
"We asked them many times for weapons but they gave us only promises."
The BBC's Orla Guerin, in Baghdad, says mass killings of the tribe have become an almost daily occurrence.
Tribal leaders said Sunday's victims, who reportedly included 10 women and children, were lined up and publically shot as punishment for what IS sees at the tribe's resistance.
A number of people from the Al-Bu Nimr tribe were also found dead in mass graves earlier this week. Fifty others were killed on Saturday.
The latest shootings occurred in the village of Ras al-Maa, north of the provincial capital Ramadi.
A local official told the Associated Press news agency that many members of the tribe fled there from near the town of Hit, which was captured by IS last month.
The Al-Bu Nimr tribe had joined the Iraq government campaign against IS in Anbar, much of which is now under jihadist control.
The recently-formed and Shia-dominated Iraqi government is trying to win over Sunni tribes, which it sees as a key element in the fight against IS.
But Baghdad has not yet succeeded in persuading the bulk of the tribes to turn on IS.
The Associated Press reports that just 5,000 of an estimated 30-40,000-strong tribal population are backing the Baghdad government.
The tribes want guarantees that they will be given a serious degree of devolution for their areas and a real say in national decision-making, correspondents say.


Sean Ervine hit a fine century to help put Hampshire in a strong position against Warwickshire on day three.

The visitors looked in trouble when Rikki Clarke (3-63) dismissed Liam Dawson and James Vince in successive deliveries to leave the score at 58-3.
However, Michael Carberry (81) and Ervine (102) batted superbly to ensure the away side reached 339 all out.
Warwickshire finished the day strongly to reach 47-0 and leave an intriguing final day in prospect at Edgbaston.
Hampshire began the day on 38-1 and saw off the opening bowlers before Clarke struck twice in two deliveries.
First Dawson cut the ball straight to Sam Hain at point before Vince was trapped lbw for a golden duck.
With wickets falling around him, Carberry continued his excellent form against Warwickshire, hitting 10 fours and a six before playing onto his stumps to become Clarke's third victim.
Ervine was then well supported on the way to his 17th first-class century by Gareth Berg (36) and Danny Briggs (33), as Hampshire frustrated the hosts and stretched their lead beyond 300.
Warwickshire openers Varun Chopra and Ian Westwood (37) made a positive start to the run chase to leave them 332 runs from victory.
Warwickshire all-rounder Rikki Clarke:
"It's evenly poised. We will have to bat well. It will be a tough chase, but Division One cricket is tough.
"It is good that we came through unscathed tonight and now we have just got to bat well tomorrow and get the job done.
"Batting has been tricky at times but less so at others on a slowish pitch. The new ball has a bit of carry but after about 25 overs it becomes quite a difficult wicket to get people out on."
Hampshire centurion Sean Ervine:
"Most of the time I just try to play positively and it worked well for me today. It was a good day for us.
"We had a tough morning but then recovered well. We have put ourselves in a position where we could win the game or get a good draw.
"It is going to be a good contest. The wicket is still playing reasonably well but there is a bit of variable bounce there.
"Also we have got a lot of swing-bowlers in the team and I believe the weather forecast is for overcast tomorrow so we could get some help there."


A car ploughed into a row of shops in Reading, causing structural damage.

The crash happened on the A329 Oxford Road, at about 05:30 GMT.
Police said two of three people in the red Peugeot 206 involved were being treated in hospital.  A fourth is being sought by police.
The road has been closed while a structural engineer assessed the safety of two buildings, a hairdressers and a charity shop.
Thames Valley Police said inquiries were ongoing to establish the circumstances of the crash. No arrests have been made.
Motorists were advised to find alternative routes as lengthy delays were expected.  A diversion has been put in place.


Jono Gibbes is to become the head coach of Pro12 side Ulster on a two-year deal in the summer.

The 40-year-old former New Zealand player is currently forwards coach at Clermont Auvergne and he previously held a similar position at Leinster.
Gibbes will work under director of rugby Les Kiss, while current head coach Neil Doak's future is unclear.
"The respect I have for Les as a coach and person was one of my main reasons for making this decision," said Gibbs.
Ulster are sixth in the Pro12 table and out of the European Champions Cup in what has been a largely disappointing season.
"Les sold his vision of where he wants to take Ulster over the next few years," added Gibbes.
"Ulster is a team that I know well, having come up against them on a number of occasions. The Clermont-Ulster games this season gave me an insight into the strengths of the squad and it's exciting to think that I'll be part of that environment from next season."
Gibbes, who joined Leinster in 2008 and won three Heineken Cups during his spell in Dublin, said: "With six years at Leinster and three at Clermont in the Top 14, I've been afforded many different experiences, working with some very talented coaches and players.
"I hope to apply what I've learned to the role at Ulster and my family and I are looking forward to integrating into a strong community in Belfast."
He moved to France in 2014 and was part of a coaching set-up that guided Clermont to the Top 14 and Champions Cup finals in his debut season.
"Jono's CV speaks for itself and I know that he's looking forward to joining Ulster and working with the team," said Kiss, 52.
"Since his retirement from playing, Jono has had an integral role in the coaching teams of two of European rugby's most successful sides.
"Jono's expertise as a forwards coach is obvious, however his wealth of knowledge in other areas of the game will be really important for us."
"A review of the coaching structure is ongoing ahead of next season and the appointment of Jono as head coach is the first part of that process.
"A further announcement will be made in the coming weeks, which will focus on getting the right balance in our coaching team."


Boris Johnson, the Mayor of London, gave evidence to the House of Commons Treasury Select Committee on Wednesday morning about the effects of Britain leaving the European Union.

He was challenged on a number of claims Reality Check's taken issue with in the past. Just to be clear: Children under the age of eight are not banned from blowing up balloons in the EU; nor is there a ban on recycling teabags.
Today another claim came to the fore. Andrew Tyrie, the chairman of the Committee, questioned a claim from Mr Johnson's book Lend Me Your Ears that there is EU legislation on the weight, size and composition of coffins. Mr Johnson maintained it was true and that it had led to a standardised 'euro-coffin'.
Mr Tyrie said there wasn't any EU regulation at all. There is a Council of Europe convention on the transfer of corpses across borders but there is no EU legislation, and the UK isn't a signatory to the convention anyway.
He said the story was a figment of Mr Johnson's imagination but Mr Johnson insisted that his memory was that there was EU legislation. He was asked to provide evidence after the session.
The convention referred to by Mr Tyrie is the Agreement on the Transfer of Corpses signed in 1973. As he said it's a multilateral treaty of the Council of Europe, not the EU, about the international transfer of corpses; and the UK is not a signatory.
In any case, while it does specify that coffins used to transport corpses should be watertight and meet minimum quality standards (including options on the thickness of wood used) it doesn't specify size limits.
The European Commission did propose a draft directive covering the same issue in 1992 but it wouldn't have had an impact on coffins used for funerals in member states and it never went ahead with the plan, in part because it contravened the principle of subsidiarity.
REALITY CHECK VERDICT: As Mayor Johnson might say - piffle. There isn't, and never has been, any such regulation.
READ MORE: The facts behind claims in the EU debate


David Cameron's major policy speech on the challenges posed by Islamist extremism has been hailed in some quarters as a nuanced intervention in a complex and sensitive area, as well as attracting criticism from some others, including parts of the British Muslim community.

The prime minister's speech is interesting in a number of ways, including the light it inadvertently sheds on the ongoing political challenge posed by the growth in extremism in the last decade or more.
His speech contained some echoes of one made almost 10 years to the day by one of his predecessors.
In August 2005, Tony Blair, in the wake of the 7/7 bombings in London, declared that "the rules of the game have changed".
His policy response was a raft of new anti-terror legislation as well as new laws to combat extremists.
The plans included measures to deport extremist foreign Muslim clerics without appeal, shut down mosques preaching hate, and proscribe extremist Muslim groups.
Mr Blair also proposed a commission to look at multiculturalism but said that it would not threaten anyone's culture or religion.
But he went on: "There are people who are isolated in their own communities.... That worries me because there is separateness that may be unhealthy."
These very themes were touched on by Mr Cameron on Monday.
In another key part of his speech, Mr Cameron said he would actively encourage reforming and moderate Muslim voices to speak up.
The prime minister said he would set up a new community engagement forum to hear directly from Muslim groups challenging extremism.
Looking back to November 2005, a number of working groups set up in the wake of the London attacks put forward proposals of their own to tackle extremism and the radicalisation of young Muslims.
Their proposals, which found favour with then Home Office Minister Hazel Blears, included a rapid rebuttal unit to combat Islamophobia, a better reflection of Islam in the national curriculum, and better training of imams.
The renewed emphasis on shared values as a way of combating extremism touches on ideas that came up back in 2009, as part of the Prevent initiative, ostensibly aimed at tackling the threat of radicalisation among young Muslims in particular.
The new measures, put forward in the Queen's Speech in May, reinforce the growing tendency towards more legislation in the sphere of anti-terrorism.
Indeed the UK has a long - if controversial - history of terrorism legislation.
The last Labour government introduced five major pieces of terrorism legislation:
The political in-fighting, particularly over the issue of detention periods for suspects, was fierce.
David Cameron returned to another of his major themes in linking the extremist threat to values and identity.
Mr Cameron explored some of these ideas in a major speech in Munich in 2011, dubbed by some at the time as an example of a new "muscular liberalism".
It was in Munich that he stated that "the passive tolerance of recent years" had to be replaced by a much more assertive defence of British values against "Islamist extremism".
He talked about the notion that the problems stemmed in some instances from a failure to fully belong in British society.
Asking that Muslims, particularly moderate ones, play a greater role in finding the solution to the Islamist threat has again been highlighted as a major plank of government policy.
It has been a common theme over the last decade or more. In January of this year, Communities Secretary Eric Pickles wrote to more than 1,000 imams and Muslim leaders, urging them to publicly condemn the attacks on Charlie Hebdo and a kosher supermarket in France.
Mr Pickles pointed out in his letter that Muslim leaders had a responsibility to prevent young people from being radicalised.
Mr Pickles was criticised by some Muslim leaders for his approach - they believe their efforts go unrecognised and that such statements stigmatise the Muslim community unfairly.
But the prime minister backed Mr Pickles, claiming that some Muslims had " a problem" if they objected to being asked to do more to tackle Islamist extremism.
Mr Cameron, in his latest speech, put his weight behind setting up a number of new de-radicalisation initiatives.
The government already has a de-radicalisation programme - Channel - which is part of the Prevent strategy to help stop people becoming involved in violent extremism.
The government's overall strategy for countering terrorism - Contest - is based on four areas:
The government is committed to publishing regular updates on the Contest strategy. The most recent covers the year 2014.
Mr Cameron speaks of the fight ahead as a generational struggle against Islamist-inspired terrorism.
And his speech on Monday, agree supporters and critics alike, is his attempt to show the way forward.


League Two club Blackpool have denied claims they were subject of a new takeover offer.

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The Daily Mail claimed a £10m offer was made to owner Owen Oyston despite him stating the club was not for sale at a recent public meeting with fans.
Oyston was heckled throughout over the way the club is being run.
"The owners of the club have received no approach whatsoever, from any investor or third party," said a statement.
The Blackpool Supporters Trust launched a £16m bid to buy the club July 2015 but Oyston, whose son Karl is chairman, eventually ended those takeover talks.
The Seasiders, who will play in the fourth tier for the first time since 2000-01 this season, have also announced the signing of midfielder Danny Pugh.
The 33-year-old former Manchester United trainee joins on a free transfer after his release by Bury and has signed a one-year deal, with further 12-month option.
"He brings a wealth of experience to the team and will be a strong, vocal presence in the middle of the park," said boss Gary Bowyer.


Japanese stocks traded higher on Friday, shrugging off weak trading on Wall Street.

US markets had fallen again on Thursday as investors mulled the possibility that the US Federal Reserve might raise interest rates as soon as June.
Tokyo's Nikkei 225 index closed up 0.5% at 16,736.35.
Shares in exporters were lifted after the dollar remained stronger against the yen. Toyota rose 1.2% while Nissan was 0.9% higher.
Investors are watching the G7 meeting in Japan starting on Friday, which is expected to take up currencies as a topic.
In China, Hong Kong's Hang Seng rose 0.8% to 19,852.20, while the mainland's benchmark Shanghai Composite closed 0.7% higher at 2,825.48.
In South Korea, the benchmark Kospi index closed flat at 1,947.67.
Australia's ASX/200 index climbed 0.6% to finish the day at 5,357.10.  Shares in commodity giant BHP Billiton rose 1%, while Rio Tinto closed more than 2% higher.


Arsenal will face holders Barcelona in the Champions League last 16.

Chelsea have been drawn against Paris St-Germain for the third consecutive season, while Manchester City face Dynamo Kiev.
Roma versus Real Madrid and Juventus, last year's beaten finalists, against Bayern Munich are two of the standout matches in the draw.
First legs are scheduled to take place on 16-17 and 23-24 February. Return legs are on 8-9 and 15-16 March.
The winners of each group, including Chelsea and Manchester City, are at home in the second legs, while Arsenal will host their first leg.
Barcelona v Arsenal is a repeat of the 2006 final, which the Spanish champions won 2-1 thanks to two late goals in Paris.
PSG, who are 17 points clear at the top of the French league, knocked Chelsea out on away goals at this stage last season, while the Blues beat them on the same rule in the quarter-finals the previous year.
Dynamo Kiev beat Manchester City in the 2010-11 Europa League last 16, with striker Mario Balotelli sent off for the English side.
The first leg in Kiev will be played in a stadium without any supporters present, as Dynamo Kiev were punished following racist attacks on fans during a group game against Chelsea.
The draw for the quarter-finals will be held on 18 March with the semi-final line-up drawn on 15 April.
Gent v Wolfsburg
Roma v Real Madrid
Paris St-Germain v Chelsea
Arsenal v Barcelona
Juventus v Bayern Munich
PSV Eindhoven v Atletico Madrid
Benfica v Zenit St Petersburg
Dynamo Kiev v Manchester City


There are a couple of snags with the idea that a democratically-elected executive mayor will take control of the new powers being handed down from central government to the nine councils agreeing to be part of the Sheffield City Region.

First, a third of the electorate will not be allowed to vote for the new mayor in the polls scheduled for 2017.
Secondly, the mayor's powers will not cover the entire region.
Funnily enough, neither of these issues was given much prominence in the avalanche of press releases and interviews on the day the deal was announced on 2 October.
George Osborne himself, on a high-profile flying visit to Sheffield to sign the deal with council leaders, called it the biggest reform of local government in a generation.
"For local people it will mean the decisions that affect them being taken locally," he said.
He never mentioned that only some "local people" will be part of the democratic process in electing a mayor.
So why is it that this first step since the Chancellor appealed to councils across the country to join his "devolution revolution" appears to be heading straight into a muddy political puddle?
The template was for a "Boris Johnson-style" powerful mayor using the authority of a mandate from the local electorate to boost the economy of a cluster of neighbouring local authorities.
The mayor would control transport and travel policies, drive inward investment and industrial training, as well as keeping the police on their toes by replacing the Crime Commissioner.
That was exactly how devolution was sold to Greater Manchester last year and was the basis of the 38 separate bids that emerged this spring from different permutations of local councils across the country for a similar deal.
That template has cracked at it first outing because creating devolution is proving far more complicated than drawing up a boundary on a map.
The Sheffield City region highlights the problem.
It is made up of four South Yorkshire authorities: the city itself together with neighbours Barnsley, Doncaster and Rotherham.
As their combined population of around 1.3 million was not considered big enough to create a viable economy the adjacent smaller councils of Bassetlaw, Bolsover, Chesterfield, North East Derbyshire and Derbyshire Dales were persuaded to sign up and add a further half million people.
However, those smaller authorities are over the border from South Yorkshire where legal control of public transport and highways budgets are in the hands of the county councils of Derbyshire and Nottinghamshire.
Those county councils have absolutely no intention of handing over a single drop of their powers to the new devolved region about to move in next door.
So the confusing compromise is to totally exclude the voters who live in those smaller councils from the mayoral election.
That same boundary dispute complication completely knocks out the idea of the Sheffield Mayor becoming Police and Crime Commissioner as both Nottinghamshire and Derbyshire have their own separate forces.
Is this a unique problem for the cross-border Sheffield City Region?
The answer to that lies up the road in the ambitions for a mayor-led Leeds City region.
At its heart are the five West Yorkshire local authorities of Leeds, Bradford, Calderdale, Kirklees and Wakefield.
However, it also plans to slip over into North Yorkshire to take in the smaller authorities of Harrogate, Craven, Selby and the City of York.
To say that North Yorkshire County Council, the current transport and highways authority, is not amused by this proposal would be something of an understatement.
Not surprisingly, so far there is no indication of when, or even if, the announcement over the creation of the Leeds City Region will be made.


Josh Simpson scored a late equaliser for Plymouth against fellow promotion hopefuls Bristol Rovers but Argyle dropped to second place in League Two.

Gregg Wylde almost scored for Plymouth in the first half of the West Country derby, but shot over from 15 yards.
And after Tom Lockyer hit the post for Rovers, Billy Bodin nodded them ahead from Jermaine Easter's cross.
But with two minutes of normal time left, Simpson drilled in from the edge of the area to earn his side a point.
The result left Rovers in fourth place, four points behind the automatic promotion places, while Plymouth are two points behind leaders Northampton, who have a game in hand.


South Korea's currency slipped in value after the country's central bank unexpectedly cut its benchmark interest rate to a new record low.

The won fell 0.3% against the US dollar after the Bank of Korea cut the seven-day repurchase rate by 25 basis points to 1.25%.
The Kospi stock index fell 0.14% to close at 2,024.17 points.
Analysts say that there could be further rate cuts in the coming months as the economy is in a weak state.
"As things stand, the economy is already in a fragile state and could certainly use more support," said Krystal Tan from Capital Economics.
Other Asian stock markets are erasing earlier gains and falling following subdued Chinese inflation data.
Consumer prices on the mainland rose 2% in May from a year earlier, compared to estimates of a 2.2% increase.
Producer prices fell by 2.8% which was below estimates for a fall of 3.2%.
Japan's Nikkei 225 ended 1% lower at 16,668.41 while the broader Topix also lost 1% to shut at 1,337.41.
Over in Australia, the ASX 200 index slipped 0.15% to 5,361.
New Zealand's main index fell 0.3% to close at 6,970.55 after its central bank kept interest rates on hold due to concerns about rising home prices.
Markets in China, Hong Kong and Taiwan are closed for a public holiday.


A man who fled the country following the death of a university graduate has been found guilty of manslaughter.

Anton Levin, from Dagenham, was stabbed at a house in St Anns Road, Southend on 19 November 2014.
Abdulfatah Suleiman, 28,  was arrested in Norway and extradited back to the UK where he was convicted by a jury at Chelmsford Crown Court.
Three others were convicted for their parts in Mr Levin's death in June.
Danielle Russell, 27, from Southend, and two teenage boys were found guilty of manslaughter, conspiracy to commit GBH on another man and conspiracy to commit robbery.
Russell was jailed for 11 years, and the teenagers, who can't be named for legal reasons, to ten years, four months with a five-year extended licence.
Investigating officer Det Con Jo Cane said Suleiman had "stabbed Anton Levin and then fled the country".
A warrant was issued for his arrest and on 19 June he was arrested in Norway and extradited back to the UK.
"While the other defendants had been found guilty of manslaughter the person who actually stabbed Anton had evaded capture," Det Con Cane said. "Now his trial has been completed. the verdict cannot bring Anton back, but gives closure enabling the family to grieve for their losses knowing that he will be jailed alongside the others also found guilty."
Suleiman is due to be sentenced in March.


A company which intends to invest in Northern Ireland businesses is to be listed on the stock market in London.

Rockpool Acquisitions will be a so-called 'cash shell' which will raise money from shareholders and then buy a business or businesses.
It said it has no specific targets yet, but will look at acquisitions of up to Â£20m which could benefit from at least Â£1m of additional working capital.
The company expects its shares to start trading on 5 July.
The director of Rockpool Acquisitions are Mike Irvine, a Belfast corporate financier; Richard Beresford, a London lawyer; and Neil Adair, who at one time ran the operations of Anglo Irish Bank in Belfast.
Mr Irvine said: "Our decision to list on the London Stock Exchange makes both strategic and commercial sense as we believe that there are a number of excellent Northern Ireland based companies that would benefit from access to the deeper pools of capital that a listing provides.
"The Northern Ireland business community has a strong heritage of entrepreneurship but has not necessarily taken full advantage of the public markets."
Rockpool aims to make its first acquisition within 12 months of listing.


Dressed in baggy jogging bottoms and a white vest, with headphones thrown around his neck, a young man collects a coffee from the self-service machine, completes a lap of the store, buys nothing, and walks out.

He is a Waitrose loyalty card carrier making the most of the free hot drink offer.
Not the image of stereotypical Waitrose clientele perhaps, but certainly typical of the new breed of "promiscuous" customer who tours various stores for a good deal.
So, will his apparent disloyalty by shopping around lead to the end of loyalty cards - which reward shoppers who spend plenty and regularly in the same supermarket?
This month, Sainsbury's is halving the reward points available to Nectar card holders. Some of the increasingly successful chains do not bother with a loyalty card at all.
But some experts argue that reports of the loyalty card's death are greatly exaggerated. Instead, they expect a rebirth, from purse-clogging plastic cards to a digital format with some entertainment value. Also, the data they hold might even help protect our environment.
Loyalty points, or trading stamps, have been around for decades. Among the best remembered are Green Shield Stamps. Lick and stick the stamps in a saver book and choose anything from a mouth organ to a motor boat from the catalogue.
The modern-day loyalty card was born in 1995 with the hugely successful Tesco Clubcard.
It was launched after the brains behind the concept - Edwina Dunn and her husband Clive Humby - gave a presentation to the Tesco board, explaining how they could analyse data to work out the spending patterns of customers.
The reaction of the Tesco chairman of the time, Lord MacLaurin, was to say: "What scares me about this is that you know more about my customers after three months than I know after 30 years".
The modern loyalty card works with a simple trade. By handing over their card at each shop, the consumer agrees to give the retailer access to useful data - including their age, when they shop, what they buy and how often. Such detail is key for cutting costs and maximising revenue in distribution and promotion.
In return, the shopper gets discounts and special offers.
Aimia - the company that runs the Nectar card - claims:
After the Tesco Clubcard came the Nectar card, which can be used across a variety of outlets, followed by a plethora of others, including the widely used Boots Advantage card.
In fact, within 100 yards of the aforementioned Waitrose store, shoppers can pick up at least three other branded loyalty cards.
But do they attract extra custom?
A completely unscientific survey, conducted from a cafe opposite, revealed that more than half of those exiting the Waitrose store with a takeaway cup had not bought anything from the store - each representing a financial loss for the supermarket.
Waitrose recently changed the deal that had seen it give away a million cups of tea and coffee a week. Cardholders drinking their free brew at the in-store cafe must now buy a "treat" too.
Meanwhile, from 11 April, Sainsbury's will award Nectar cardholders one point, not two, for every Â£1 spent.
This, according to retail analyst Natalie Berg of Planet Retail, is a response to the threat from discount chains such as Aldi and Lidl. Price is more important than loyalty.
"Consumers today are promiscuous; they shop around for the best deals," she says in her blog.
"They often visit more than one supermarket on the same day and increasingly this involves a trip to the discounters. So, the idea of being loyal to a particular grocer is a thing of the past. People no longer think of themselves as an Asda shopper or a Tesco shopper.
"They are buying little, often and across a multitude of supermarket brands. Cue the death of the weekly shop and supermarket loyalty."
She says that loyalty cards, which are expensive to run, add an extra layer of complexity for shoppers who just want bargain prices.
David Black, of analysts Consumer Intelligence, says that it is only really worth customers getting a loyalty card if they are shopping in the store anyway. Comparing prices across different outlets, then buying at the cheapest, is the better money-saving option.
"Loyalty cards make an awful lot of sense for the retailers, but they are less attractive for card carriers," he says.
So does this spell the end for loyalty cards?
Their demise has been predicted for a long time. A news story on the BBC News website in 1999 was headlined "Loyalty cards losing appeal", reporting that researchers had found "a third of people preferred low prices to points or other incentives".
But Annich McIntosh, editor of Loyalty Magazine, says that whatever the disloyalty of the price-savvy consumer then and now, rewards schemes are here to stay.
She points to airlines and hotels where loyalty schemes, such as air miles, have been vital for profitability. Many women, she adds, have an "emotional engagement" with their Boots card.
What does that mean? Many customers save up their Boots reward points, she says, then use them to get a luxury beauty product to spoil themselves - something that they would not otherwise have bought.
That tends not to be the case with mildly annoying supermarket cards, with complex rules on redeeming points.
"Supermarkets rested on their laurels for a while. They have been taken by surprise by the budget stores," says Ms McIntosh.
Supermarkets still need that useful data, she says. Morrisons launched its own loyalty card scheme in October last year. Even the discount stores need data, although they buy it in from consumer research companies, rather than harvest their own from loyalty cards.
Ms McIntosh says that these cards need to become more relevant by personalising offers, rather than just rewarding bulk spending, and by embracing new technology.
It is logical to predict that instead of shoppers handing over a plastic card at the till, their smartphones will recognise they are in the store and ping over an electronic voucher for their favourite brand of tea.
A big area of growth is the use of games on smartphones to encourage young consumers to share vital shopping data.
"If you want to know from teenagers what their most-wanted item of clothing is, then engage them with a game. It really is very popular among consumers who won't be wowed with 10p off their shop," says Ms McIntosh.
Some academics argue that the end of loyalty cards would also mean the end of a rich collection of data that can be used to benefit society.
These cards provide specific detail on spending habits - highlighting the difference between what people say they do and their actual behaviour.
Professor Mark Birkin, from the University of Leeds and director of the Consumer Data Research Centre, points to the example of health and nutrition.
The consumption patterns revealed through loyalty card data may reveal how truthful consumers are about their (un)healthy eating habits.
His centre has deals with some supermarkets which provide anonymous spending data for specific research.
So, the next time city planners consider where to build roads based on travel patterns, where to target health awareness based on eating habits, and how to protect the local environment based on packaging rubbish, the chances are that the information on that plastic loyalty card found in your purse or wallet will help to inform their decisions.


The bells of two fishing vessels which were involved in the Cod Wars are to be exchanged in a gesture of cooperation.

Hull trawler Arctic Corsair was rammed by the Odinn when Iceland imposed a limit on how much fish could be caught in its waters in the 1970s.
Ex-fishermen and civic leaders from Hull are heading to Iceland on Wednesday for a four-day trip to meet veterans from the Icelandic boat.
Hull City Council said it would "offer a hand of friendship from both sides".
Icelandic councillor Elsa Yeoman, chairperson of culture and tourism in Reykjavik, said: "Reykjavik and Hull share a long history based on the importance of fishing.
"Now, with the rivalries of the past squarely behind us the two cities engage in a relationship based on respect, friendship and trust that is deeply rooted in our shared history - and sacrifices to the sea."
Councillor Terry Geraghty said: "For many years fishing vessels from all over the world exploited the rich waters around Iceland and this special visit will offer a hand of friendship from both sides of the Cod Wars."
The trip is also part of a project by Hull Museums on the history between Iceland and the UK during and after the Cod Wars, the authority said.
Assistant Curator Tom Goulder said: "An important part of the trip for the Hull ex-fisherman is the chance to reflect with Icelandic counterparts on the relationship between the two countries and the shared history of lives lost at sea."
According to National Historic Ships UK, Arctic Corsair broke the world record for landing the most Cod and Haddock fish from the White Sea in 1973.


Conservative Katy Bourne has been re-elected police and crime commissioner for Sussex.

Ms Bourne, who became Sussex's first PCC in 2012, was declared winner after the vote went to a second count.
Three candidates were eliminated in the first count, leaving only Ms Bourne and Labour's Michael Jones.
In the first count, Ms Bourne had 114,570 votes and Mr Jones had 61,017. The second count brought their totals to 139,335 and 86,392 respectively.
She said:  "I'm absolutely honoured and very privileged to be elected."
She said she needed to "find extra savings because budgets are still reducing" and "to invest in frontline policing because I know that is really important to people in Sussex".
Voter turnout was 22.5% compared with 15.3% in 2012.
The three eliminated in the first count were Green Party candidate James Doyle, UKIP's Patrick Lowe and James Walsh from the Liberal Democrats.
Results listed alphabetically by surname are as follows. BBC News App users: tap here to see the results.


A 1950s delivery van rebuilt with bodywork from a salvage yard was unveiled at Crufts - after its owner ignored calls to scrap it.

The Morris Commercial J-Type belonging to Lincolnshire-based Laughing Dog farm bakery went on show at the NEC.
Its 1,750-hour restoration was overseen by 27-year-old William Grant, who named the van after his grandfather Ted Grant OBE, who set up the company.
Its 40mph top speed - slower than some greyhounds - rules out long journeys.
"It's almost dangerously slow now and it will be owned by the factory and used as a promotional vehicle," said Mr Grant.
The restoration at Laughing Dog's site in Old Leake, near Boston, went ahead despite the front of the 1.5-litre J-Type - bought in 2013 - being badly rusted.
Mr Grant sourced a rear section from a scrapyard in Stoke-on-Trent and reproduced other panels using more than 20 sheets of mild steel.
The new panels were shaped by hand to produce parts indistinguishable from factory-made equivalents fashioned in 1951.
Asked how the van performs when driven, Mr Grant added: "It's very, very noisy. It's got a very high back axle ratio, so it accelerates quickly but has a top speed of about 40mph.


An Australian plane passenger, who claims he suffered back pain after being seated next to an overweight man, is suing Etihad Airways.

James Bassos says he had to contort his body to avoid contact with his fellow passenger during a 14-hour flight from the United Arab Emirates to Sydney.
He said the journey resulted in a back injury and is claiming $227,000 (Â£106,000) in damages.
Etihad insisted it would continue to oppose the case.
"Mr Bassos will finally face a medical assessment in December 2015," the company said in a statement.
"We believe that the matter will proceed to an early conclusion."
Etihad had attempted to get the lawsuit, which was filed in 2012, thrown out of court.
But a judge refused its request on Thursday and ordered Mr Bassos to undergo a medical assessment.
The 38-year-old designer from Brisbane claimed he had to twist his body to avoid touching the "grossly overweight" passenger, who was encroaching on his seat.
After five hours of pain and discomfort, he asked to be moved, but was told the flight was full, he said.
He was eventually allowed to sit in a crew seat at the back of the aircraft, but had to return to his original spot for landing.
Etihad said it was common for customers to be seated next to overweight passengers on a fully booked flight.
Mr Bassos claims he still suffers back pain and his sleep and concentration have been adversely affected.
He is suing for medical expenses and loss of earnings.


Police have confirmed that the body of a man found at Cave Hill in north Belfast on Saturday was that of missing Newtownabbey man Dean McIlwaine.

Mr McIlwaine was last seen in the Carnmoney Road area of Newtownabbey in County Antrim on Thursday 13 July.
His family has thanked all those who were involved in the search for the 22-year-old.
His parents led a public search for their son on Saturday.


A broken pool cue used as a prop in the Trainspotting sequel has sold for £750.

The cue used to attack Ewan McGregor's character Renton was one of hundreds of props from T2 Trainspotting auctioned for charity.
Bidding on the item featured in the sequel to the 1996 hit smashed the estimated selling price of £70-£90.
A steel prison toilet from jail scenes featuring Begbie, played by Robert Carlyle, sold for £550, more than seven times the top estimate of £70.
The entire bar from the Port Sunshine, the Leith pub run by Johnny Lee Miller's character Sick Boy, sold for £1,200, while the red sofa from his flat sold for £880.
Proceeds from sale at Mulberry Bank Auction House in Glasgow will be split between Glasgow charity Calton Athletic, which helps rehabilitate people with drug and alcohol addictions, and Edinburgh-based youth charity The Junction, which has Trainspotting author Irvine Welsh as patron.
A staff member at the auction house said: "The pool cue surprised everybody, going at £750. The auction has been exceptionally well-received and interest has far surpassed what we would have expected."
T2 Trainspotting was released earlier this year, 21 years after the original film followed the lives of a group of heroin addicts in Edinburgh.
The sequel, which revisits  the same characters in middle age, has been warmly received by critics.


A sugar shortage has forced Coca-Cola to stop producing soft drinks in Venezuela amid an escalating food and energy shortage.

Coke said that suppliers in Venezuela will "temporarily cease operations due to a lack of raw materials".
The announcement comes after the country's biggest brewer, Empresas Polar, closed plants due to a barley shortage.
Venezuela's economy has contracted sharply as oil prices plunge.
A Coca-Cola spokesperson said the company would continue producing sugarless drinks such as Coca-Cola Light (Diet Coke).
"We are engaging with suppliers, government authorities and our associates to take the necessary actions for a prompt solution," she said.
Sugarcane production has been falling due to price controls and rising production costs, as well as problems in obtaining fertiliser.
As a result, many smaller farmers have turned to other crops that are not price controlled and thus generate higher income.
Venezuela is expected to produce 430,000 tonnes of sugarcane in 2016/17, down from 450,000 tonnes for the previous 12 months, and import 850,000 tonnes of raw and refined sugar, according to USDA figures.
The economic problems have forced many consumers to queue for hours to buy basic foodstuffs.
Venezuela's economy is expected to shrink by 8% in 2016 after it contracted by 5.8% last year.
Its reliance on oil to generate foreign currency and investment has made it a victim of regular recessions.
President Nicolas Maduro has instituted a state of emergency in an effort to combat the economic crisis. Critics argue it is an attempt to strengthen his grip on power.
Meanwhile, tyre maker Bridgestone said on Monday it was selling its Venezuelan business after six decades in the country.
The company's Venezuelan assets will be sold to Grupo Corimon.
Other multinational firms such as Ford, Procter & Gamble and Halliburton have either slowed or abandoned their investments in Venezuela.


US President Donald Trump has launched an extraordinary attack on a female news anchor's alleged plastic surgery.

He said MSNBC host Mika Brzezinski was "bleeding badly from a face-lift" during a visit to his Florida golf resort Mar-a-Lago.
In a Twitter salvo, Mr Trump also assailed Brzezinski's MSNBC co-presenter Joe Scarborough.
They are both his occasional sparring partners and she this week accused him of developing a "dictatorship".
"I heard poorly rated @Morning_Joe speaks badly of me (don't watch anymore)," Mr Trump tweeted on Thursday morning.
He also accused "low I.Q. Crazy Mika" and "Psycho Joe" of "insisting on joining me" at Mar-a-Lago over three days at New Year's Eve.
"She was bleeding badly from a face-lift. I said no!" he added.
Amid an outpouring of criticism from left and right, the White House rejected suggestions Mr Trump had done anything wrong.
"The president has been attacked mercilessly on personal accounts by members on that programme," deputy press secretary Sarah Huckabee Sanders told a news briefing.
"And I think he's been very clear that when he gets attacked he's going to hit back.
"The American people elected someone who's tough, who's smart and who's a fighter.
"And that's Donald Trump. And I don't think that's a surprise to anybody that he fights fire with fire."
Brzezinksi, 50, hit back earlier by tweeting an advert for a children's cereal, with the caption, "made for small hands", an apparent reference to a taunt often directed at Mr Trump by his critics.
During his presidential campaign, Mr Trump was a frequent guest on MSNBC's Morning Joe programme, which was accused by liberal voices of giving him preferential treatment.
But the relationship turned sour as the presenters sharpened their scrutiny of the candidate.
The pair have stepped up their attacks since Mr Trump's inauguration, deriding him as a "fake president".
In recent weeks, Scarborough has called Mr Trump a "bumbling dope", resembling "a kid who pooped in his pants", while Brzezinksi has mocked members of the administration as "lobotomised".
Mr Trump's latest broadside comes just a month after Scarborough and Brzezinski, who are engaged to one another, told Vanity Fair magazine the president had offered to officiate at their wedding.
She is the daughter of the late Zbigniew Brzezinski, who was an aide to Presidents Carter and Johnson, while Scarborough is a former Republican congressman.
Let's quickly review all of the people who have told Donald Trump to tone down his tweets as president. His wife. His White House advisors. His lawyers. Republicans in Congress. Even his own supporters have said they think his social media fusillades are counterproductive.
Yet here we are again. Another morning, another round of intensely personal Twitter invective that marks a dramatic departure from the (at least public) behaviour of past occupants of the Oval Office.
That this comes as no shock may, in fact, be the biggest shock of all. Mr Trump mocked people's looks (Rosie O'Donnell) as a businessman, and he was rewarded with reality television show stardom. He mocked people's looks (Carly Fiorina, Rand Paul) as a candidate, and he was rewarded with the presidency. Now he's mocking people's looks from his new home in the White House.
The president has hit the hornet's nest again, and he'll be roundly condemned by media commentators and Democrats. Republican politicians will express concern, then go back to their conservative legislative efforts.
This, too, will pass. As will the next round. Until the American voters - the only ones, it seems, with the real power - decide they want a change.
Mr Trump's tirade comes weeks after Ivanka Trump complained about nasty attacks on her father.
"There's a level of viciousness I wasn't expecting" in Washington DC, the first daughter told Fox News.
Online critics have noted the president's wife, Melania Trump, expressed a desire during the election to campaign against cyber-bullying.
But her spokeswoman, Stephanie Grisham, said in a statement on Thursday: "As the First Lady has stated publicly in the past, when her husband gets attacked, he will punch back 10 times harder."
The Democratic National Committee described Mr Trump's tweet as "an attack on women everywhere".
Paul Ryan, the highest-ranking congressional Republican, told a weekly news conference: "We are trying to improve the tone and civility of the debate.
"This doesn't help that."
When asked in the past to clarify Mr Trump's social media postings, White House spokesman Sean Spicer has told reporters "the president's tweets speak for themselves" and they should be considered official statements.
This is Mr Trump's second high-profile spat with a female news anchor.
During a US election campaign debate in August 2016, Fox News moderator Megyn Kelly asked him why he had called certain women "fat pigs, slobs and disgusting animals".
Afterwards, Mr Trump said of Ms Kelly "there was blood coming out of her eyes, blood coming out of her wherever".


Northern Ireland may never see a political figure like Martin McGuinness again, unionist leader Arlene Foster has said.

She paid tribute to the former deputy first minister at a special Assembly meeting to mark his death, aged 66.
Leaders from across the political spectrum gave their thoughts on the former IRA commander turned peacemaker.
But Traditional Unionist Voice (TUV) leader Jim Allister said "his hands drip with the blood of the innocent".
MLAs gathered at Stormont to remember the Sinn Féin figurehead, with the Assembly recalled to allow them to have their say on his impact on politics in Northern Ireland.
Mr McGuinness died in a hospital in Londonderry with his family by his side on Tuesday after suffering with a rare heart condition. His funeral will take place in his native Derry on Thursday.
Prime Minister Theresa May offered her condolences in the House of Commons.
She would not "condone or justify" the part he played in Northern Ireland's Troubles, but praised his "indispensible" role in bringing the "republican movement away from violence".
Negotiations to restore Stormont's power-sharing executive have a 27 March deadline.
It is undoubtedly the case that Martin McGuinness's funeral will mean that the time the Northern Ireland Office thought it had to continue talks before the deadline will be taken up with other matters.
What impact will this have on the chances of agreement? They seemed pretty slim prior to Mr McGuinness's death.
They still seem fairly slim, although maybe the death will inject a new mood into some of the discussions.
Speaking at Stormont, Michelle O'Neill, Mr McGuinness' successor as Sinn Féin's leader in Northern Ireland, said he had been a "political visionary", a "gifted strategist and orator", but above all "our dear and valued friend".
"His leadership and the example he set will continue to inspire those of us who are determined to build a better future for all the generations to come," she said.
She added that she would "rededicate our party to completing his life's work and to living through his legacy".
Democratic Unionist Party (DUP) leader Mrs Foster shared almost a year heading the Northern Ireland Executive with Mr McGuinness until its collapse in January.
She said his legacy was "complex and challenging" and his death had raised memories of the Troubles among the families of victims of IRA violence.
Many victims "are feeling very hurt", she added, but she also acknowledged that many nationalists and republicans were mourning "a leader, friend or mentor".
History would have the "final say" on Mr McGuinness, she added.
"It is precisely because of his past, because of his involvement with the IRA in the '70s and '80s, because of his influence within those circles, that he was able to play the role he played in bringing the republican movement towards using peaceful and democratic means," she said.
"Because of all of that, I doubt we will ever see his like again."
No-one knows how many people Martin McGuinness killed, directly or indirectly.
As a senior commander in the Provisional IRA for many years, there is no doubt there was blood on his hands.
Security sources say he went on to become chief of staff of the organisation from the early 1980s, right through until the end of the IRA's campaign of violence.
Nothing happened in Derry without him knowing.
Read more
Social Democratic and Labour Party (SDLP) leader Colum Eastwood said Mr McGuinness' "journey" began in violence but ended "grounded in the principles of peace and partnership".
He praised his fellow Derryman for his "generosity of spirit", but said victims of the Troubles should also be remembered.
Mr Eastwood told MLAs their job now was to "do what what Martin McGuinness would've wanted us to do" in breaking the political deadlock at Stormont.
Mike Nesbitt, the outgoing Ulster Unionist leader, said Mr McGuinness was "clearly a man of his word" and one of "political integrity".
"If unionism has anything to learn from Martin McGuinness it is the importance of outreach - he reached outside his comfort zone on many occasions but unionism didn't always reciprocate."
Alliance Party leader Naomi Long told the Assembly she did not believe there would have been peace in Northern Ireland had it not been for people like Martin McGuinness.
Vigils have been held in Belfast, Derry and Dublin for the lifelong republican, while books of condolence have been opened in a number of places, including at Belfast City Hall.
Mr McGuinness grew up in Derry's Bogside and at 21 years old he was he was second-in-command of the IRA in the city.
He worked at the heart of Northern Ireland's power-sharing government after the Good Friday peace agreement in 1998.
He became deputy first minister in 2007, leading the executive alongside first minister Ian Paisley - the two men had been diametrically opposed to one another in years gone by.
Among the seismic moments during his time in government was a famous handshake with the Queen in 2012 and a toast to Her Majesty at Windsor Castle two years later.
A visibly ailing Mr McGuinness stood down from his post in January in a protest against the DUP's handling of an financial scandal, in a move that triggered a snap election.
Now, without his influence, the region's political parties are faced with the job of saving Stormont amid the biggest crisis power-sharing has faced in a decade.


Actor and comedian John Sessions has criticised BBC "management culture" as "completely out of hand".

Sessions, who found fame on Whose Line Is It Anyway, said the BBC would have a better chance of survival if it was not "run like a private company".
He launched his criticism while promoting one-off BBC Two drama, We're Doomed! The Dad's Army Story.
Sessions stars as actor Arthur Lowe, who played pompous Captain Mainwaring in the classic sitcom.
Speaking after a press screening of the drama in London, Sessions said it had been shot on a "tight schedule" of two weeks instead of four. He blamed the lack of money on management decisions such as the relocation of parts of the BBC to Salford.
"I wish the executives would stop building buildings," he said. "It makes me very cross because we have to try to do our job under much more pressure than we should have to deal with.
"I don't want to sound like some whinging old luvvie, but the management culture at the BBC has become so pervasive and so money-monopolising that we are all doing these things on ridiculous schedules."
He said he hoped the current BBC director general Tony Hall would manage to "cut this management tumour down" because "it's got completely out of hand".
He went on: "This is a public broadcasting corporation - not a PLC - and the more it is treated like a corporation the better it will be and more chance it will have of surviving."
A BBC spokesman said: "We have cut senior manager numbers and costs by a third as part of our work to save Â£150m from the total paybill."
"BBC North has allowed us to get closer to our audiences and has had a huge impact both economically and culturally. The relocation was done on time and under budget and BBC North is one of the BBC's most efficient centres delivering around Â£168m cumulative savings to date."
Sessions - who also starred in BBC comedy series Stella Street and Outnumbered - considered the licence fee good value for money:  "It's the price of a very serious Christmas shop. And for that you get the most wonderful stuff throughout the year.
"Of course great things still are made. The technical quality of things is beyond belief."
Starting in 1967, We're Doomed! tells the story of how writers Jimmy Perry (Paul Ritter) and David Croft (Richard Dormer) overcame BBC management scepticism to brings Dad's Army to the screen.
Alongside Sessions, the cast includes Julian Sands as John Le Mesurier, Mark Heap as Clive Dunn, Shane Richie as Bill Pertwee, Kevin Bishop as James Beck and Keith Allen as BBC One controller Paul Fox.
The drama will screen on BBC Two before Christmas.


US Secretary of State John Kerry has said there is overwhelming evidence of Russian complicity in the downing of a Malaysia Airlines plane in Ukraine.

Mr Kerry called on Russia to take responsibility for the actions of the rebels, saying their handling of the dead had been "grotesque".
All 298 people on flight MH17 died when it was reportedly hit by a missile.
Russia has been accused of providing the rebels with an anti-aircraft system that was allegedly used in the attack.
It denies the allegations.
Earlier, the remains of up to 196 people were loaded on to refrigerated rail wagons in Torez, eastern Ukraine.
A second train has now arrived there to collect more bodies. Ukrainian officials say 251 bodies and 86 body parts have been found.
Negotiations are continuing between the authorities in Kiev and the rebels for the trains to be allowed to leave for government-held territory for identification and analysis.
Unconfirmed reports say three Dutch investigators have now arrived to the rebel-held city of Donetsk and are due to travel to Torez.
Australia's Foreign Minister Julie Bishop called on pro-Russian separatists not to use the bodies as pawns in their conflict with the Ukrainian authorities.
"There are 298 bodies on that site - their families, their loved ones want them home now," she said.
Meanwhile, Russian President Vladimir Putin said it was essential to give international experts complete security so they could conduct an independent investigation.
"It is necessary to do everything to ensure [the investigation's] full, absolute security; to provide the humanitarian corridors it needs in its work," he said.
Mr Kerry said the US had seen major military supplies moving into Ukraine from Russia in the last month, including a convoy of armoured personnel carriers, tanks and rocket launchers.
Intercepted calls suggested a Russian SA-11 missile system - also known as BUK - had been transferred to the rebels, Mr Kerry said, and the US had seen a video of a launcher being moved back into Russia after flight MH17 crashed.
"There's [an] enormous amount of evidence that points to the involvement of Russia in providing these systems, training the people on them," Mr Kerry said on a US TV network.
He also threatened further sanctions on Russia and called on European allies to get tougher with President Putin after the "wake-up call".
On Sunday, UK Prime Minister David Cameron said Europe and the West "must fundamentally change our approach to Russia" if Mr Putin "does not change his approach to Ukraine".
The indiscipline and chaos of the last two days have been replaced by the robust presence of former riot policemen who now form a cordon around the central area of the crash site.
There is still no sign of the fully fledged independent investigation which is being demanded by the international community.
During the morning local volunteers have been searching the fields. We have been told that their job is to pinpoint belongings and remains to the emergency services. But this could easily have the effect of disturbing evidence important to an inquiry.
As for the strong words from British Prime Minister David Cameron attacking Russia they are likely to have little impact on the rebels here. They are contemptuous of the West and are much more concerned with the local military balance than with any warnings from London.
Mr Kerry's comments joined a chorus of anger directed at Russian President Vladimir Putin after the rebels in charge of the crash site restricted access to the plane's wreckage and its victims.
The remains of up to 196 people were loaded on to refrigerated rail wagons at the crash site in Grabove on Sunday, three days after the Boeing 777 came down.
The freight train is now standing at Torez railway station, 15km (nine miles) from the crash site.
The carriages, with heavy closed doors, look like refrigeration units and there is the occasional smell normally associated with dead bodies, the BBC's Richard Galpin reports from Torez.
Speaking in Donetsk, the biggest rebel-held city in the east, rebel leader Alexander Borodai said the bodies would remain in Torez until international aviation inspectors arrived.
He said the bodies had been moved "out of respect for the families", adding: "We couldn't wait any longer because of the heat and also because there are many dogs and wild animals in the area."
The rebels say they will hand over MH17's flight recorders to the International Civil Aviation Organization but the US state department said rebels had tampered with other potential evidence.
Heavy machinery could be seen moving plane debris around at the crash site on Sunday.
Malaysian Transport Minister Liow Tiong-Lai, who arrived in Ukraine's capital Kiev at the weekend, said he was "very concerned" that the crash site had been "severely compromised".
A Malaysian team of 133 officials and experts, comprising of search and recovery personnel, forensics experts, technical and medical experts have also arrived in Ukraine.
But the government in Kiev says it has been unable to establish a safe corridor to the crash site for the group.
Fighting remains ongoing in eastern Ukraine between the separatist rebels and government forces in a conflict which erupted in April and is believed to have claimed more than 1,000 lives.
The passenger list released by Malaysia Airlines shows the plane was carrying 193 Dutch nationals, including one with dual US nationality.
Other victims included 43 Malaysians (including 15 crew), 27 Australians, 12 Indonesians, 10 Britons, four Germans, four Belgians, three from the Philippines, and one from both Canada and New Zealand.
Memorial services and vigils were held on Sunday in many countries, including Australia, Malaysia and the Netherlands.


A man and woman have appeared in court accused of a series of offences against a baby who is critically ill.

They were arrested on Tuesday two days after the boy was taken to hospital with cardiac arrest.
The pair, from Wolverhampton, appeared before magistrates on Thursday.
They are charged with causing grievous bodily harm, engaging in sexual activity with a child under 13 and causing or allowing a child to suffer serious physical harm.
The baby is in New Cross Hospital in Wolverhampton and remains in a critical condition, police said.
The man, aged 22, was remanded in custody to appear at Wolverhampton Crown Court on January 21.
The 18-year-old woman has been released on bail to appear alongside her co-accused.
Two other women, aged 46 and 32, have been arrested and released on bail.


Scientists say they now understand what makes a voice sound charismatic.

Some people have an innate ability to manipulate their vocal frequency to give their voice a richer quality, the US-based researchers said.
Such people can then apply additional vocal techniques to take advantage of this.
The researchers also found that political leaders with lower voices were perceived as more dominant and attractive.
Conversely, those who spoke with higher frequencies were viewed as submissive and benevolent. These findings are in line with previous research.
Controlling vocal frequency is an innate ability dependent on the size of a person's larynx.
A large larynx and long vocal fold result in a lower voice vibration. In a similar way, the same musical note will sound different played on a cello and a violin.
Leaders have the ability to manipulate their voices in order to be recognised as dominant figures, said Rosario Signorello at the University of California, Los Angeles (UCLA), who led the research.
"The internal characteristics of a dynamic or charming leader are always perceived through voice. Leaders use a charismatic voice to arouse an emotional state in their listeners," he told the BBC.
The common feature of a charismatic leader is their ability to manipulate their vocal quality in order to convey different types of charisma. In political speeches this can help persuade audiences, he said.
Speakers perceived as charismatic add inflection, harshness or other characteristics to align with their audience's expectation.
"This function is learned, dependent on the languages that we speak and filtered by the culture one belongs to," said Dr Signorello.
In the research, Dr Signorello changed the frequency of male politicians' voices from Italy, France, Portugal and Brazil, including Luigi de Magistris, Francois Hollande and Luiz Inacio Lula da Silva.
More than 250 participants in his research were then asked to rate the voices with 67 adjectives such as dishonest, scary, dynamic, attractive, convincing and fair.
The perception of a speaker was also based upon cultural preferences and the language spoken.
For example, French participants preferred a politician with a medium vocal pitch, perceiving him as prudent, calm, trustworthy and fair. Italian participants preferred a lower pitch, viewed as authoritarian, determined and menacing.
But changing one's voice to become more charismatic is not simple. Aside from one important aspect of it being innate, Dr Signorello said it also depended what type of charisma a person was seeking to portray.
"Lowering the vocal pitch, or fundamental frequency, can help to convey dominance but also sexiness. And adding a harsh voice can help [you] to be perceived as a threat or as sexy.
"A male with a low, deep voice would be perceived as dominant by other males but maybe as sexy by females. In contrast a higher vocal pitch can convey submission (male speaker, male listeners) or sexiness (female speaker, male listeners).
"So there is no general recipe for being charismatic but in every culture there are ways to manipulate your voice to convey different types of charisma."
The research from UCLA's Bureau of Glottal Affairs was presented at the 168th Meeting of the Acoustical Society of America.
Jan Schnupp, co-director of Oxford University's auditory neuroscience group said the work was interesting and fun. "Intuitively the research makes a lot of sense to me. Normally, larger people have larger, heavier vocal folds which vibrate more slowly, and therefore produce a lower fundamental frequency.
"So we associate deep voices with an impressively large physique. However, how fast your vocal folds vibrate also depends on how much muscle tension you apply in your larynx. Often muscle tone increases, and hence voice pitch rises simply when people get excited."
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The Liberal Democrats are preparing to announce whether Tim Farron or Norman Lamb will be the party's new leader.

Voting closed on Thursday afternoon in the race to replace Nick Clegg, who resigned after a disastrous general election that left the Lib Dems with just eight MPs.
The winner, who will be announced on social media, is expected to address a party rally later in the evening.
Mr Farron, the former party president, is the bookmakers' favourite.
The left-leaning Westmorland and Lonsdale MP has said he wants to focus on rebuilding the party from the grassroots up, and on issues such as human rights, the environment, and building a "fairer and more equal society".
Mr Lamb, a health minister under the coalition government, said he wanted the party to be a "consistent and clear voice" standing up a liberal society.
After a post-election surge in membership, over 60,000 Lib Dem members were eligible to vote.
Former Lib Dem chief secretary to the Treasury Danny Alexander, who lost his seat in May, used a New Statesman article to urge the winning candidate to occupy the centre ground, and not become a "sort of soggy Syriza in sandals" - a reference to Greece's anti-austerity government.
Mr Alexander said the party should not make George Osborne's Budget a "political dividing line" but instead should attack the Conservatives over civil liberties and the environment.


The number of people claiming unemployment benefits in Northern Ireland fell by 1,100 in September to 40,700.

The claimant count has now fallen by 24,000 since the most recent peak in February 2013.
The other measure of unemployment, the Labour Force Survey, fell by 0.3 percentage points to 6% in September.
That is higher than the UK unemployment rate which stands at 5.4%.
Over the quarter from June to August the number of people in employment in Northern Ireland was unchanged and has fallen slightly over the year.
The explanation for employment and unemployment falling at the same time is a rise in the number of people classified as economically inactive.
Economic inactivity refers to people of working age who are not seeking work.
It can cover students, people with health conditions, or those with caring or parenting responsibilities.
The economic inactivity rate in Northern Ireland is 27.6% compared to a UK average rate of 22.1%.


US retailer Walgreen is to pay $6.7bn (£4.3bn) for a 45% stake in UK rival Alliance Boots.

The cash and shares offer will cement Walgreen's position as the world's biggest pharmacy chain.
Alliance Boots runs a chain of chemists in the UK and more than 3,300 health and beauty retail stores in 11 countries around the world.
The company's wholesale business supplies pharmacies and doctors in 21 countries.
By Julia CaesarBusiness reporter, BBC News
Boots has been a name on the UK High Street since 1849, when it was set up in Nottingham by John Boot as a family run herbal medicine shop.
The deal between US giant Walgreen's and Alliance Boots is set to create the first global pharmacy business, with 11,000 stores in 12 countries.
Boots was bought out by private equity firm KKR for £11bn in 2007 in one of the UK's largest-ever private equity deals. KKR is in early-stage talks over an £8bn takeover of Orange and T-Mobile group Everything.
As part of the deal, Walgreen would have the option of buying the outstanding Boots shares by 2015, valuing the company at $9.5bn in total.
The Illinois-based company operates 7,890 pharmacies across the United States.
Nottingham-based Boots is smaller than its US rival but is Europe's biggest seller of health and well-being products. It also has strong internet sales.
Walgreen will pay $4bn in cash and swap more than 83 million shares for its stake in the privately-held Alliance Boots.
As a sweetener to shareholders, Walgreen raised its dividend payment from 22.5 cents to 27.5 cents.
The deal still needs to be approved by industry regulators.
The announcement coincided with the release of Walgreen's earnings for the three months to the end of May.
Net profit was $537m, down 11% on the $603m the company made in the same period last year. However, it said the stake in Alliance Boots would boost its earnings in the first year, should the deal go through.
Walgreen shares fell 6% in early trading in New York.
The deal will put Boots' major brands such as No7 cosmetics and the Botanics hair and skincare range in nearly 8,000 Walgreen and Duane Reade stores.
"I have done a deal to make Boots more visible, more international, to create new markets for Boots and for Nottingham," said Alliance Boots' executive chairman Stefano Pessina.
Walgreen's chief executive Gregory Wasson said he and his wife had been personally impressed by the No7 range.
"The UK will become the centre to develop and manufacture new products for a fantastic market like the American market. New York is the window of the world," he said.
The two companies have very little overlap. As a result, no job losses are expected from the deal. In fact, the BBC's business editor Robert Peston says the deal could create a world manufacturing centre in Nottingham, potentially increasing the number of jobs.


Residents living near a picturesque bay in County Antrim have said they are against the landing of power cables from a proposed tidal energy scheme there.

The project is being planned for the sea just off Murlough Bay - an area of special scientific interest.
But the energy company said the bay is just one of two options for bringing the cables ashore.
It said if the bay is chosen there will be conditions to the planning approval.
Patrick Casement is amongst those opposed to the cable plan at Murlough Bay.
He said laying an underground cable to a sub-station some distance away would create a "scar on the landscape that will take years to heal".
DP Energy want to build the first commercial tidal scheme in Northern Ireland and have identified an area near Fair Head.
It said it can generate enough power for 70,000 homes.
The company has two options for getting the power ashore.
The first is a cable run of 2km to Murlough Bay.
The second is a longer route covering 10km and coming ashore near Ballycastle.
DP Energy has not yet decided which it will choose.
Clodagh McGrath from DP Energy said if it gets the go-ahead the project would "have a range of conditions that have to be complied with".
So far the company has only applied for permission for the off-shore element of the project.
A range of turbines options are being considered.
Some are totally submerged, but others would have service pods protruding above the waves.
DP Energy said there will be a separate planning application for the onshore work, including the cabling, in due course.


An Australian man has taken himself to hospital after a venomous redback spider bit him on the penis.

The tradesman was using a portable toilet on a Sydney building site on Wednesday morning when he was bitten.
A spokesperson for St George Hospital confirmed that a 21-year-old man was treated for a redback bite.
The redback spider, closely related to the black widow spider, is distinguished by a long red stripe on its abdomen.
The spider's bite causes severe pain, sweating and nausea.
The BBC spoke to the owners of the property who confirmed that the man had been bitten on the penis as described in media reports.
He was later discharged from hospital in a stable condition.
Although there are recorded cases of deaths from redback bites, none have occurred since the development of antivenom in 1956.


Singer Laura Mvula has said she will not attend the Brit Awards because of "the diversity issue" and because she is not sure what going "would achieve".

The soul singer, 29, said black children were growing up feeling they were "not acknowledged in society, in media and in mainstream music".
But she told the BBC's Andrew Marr Show she may go to the awards next year if she releases an album.
The Brit Awards takes place at the O2 Arena on 24 February.
The performers at the Brit Awards, for the year's best music acts, will include Justin Bieber, Coldplay, James Bay, Little Mix, The Weeknd and Jess Glynne.
Mvula, who is from Birmingham, said of her decision not to attend the event: "Growing up my black identity is something that is hugely important to me and something that as I'm now going in to my 30s I'm thinking lots and lots more about.
"I guess the problem for me is knowing that there are young black kids growing up feeling that they're not acknowledged in society, in media and in mainstream music."
She added: "Maybe next year when I have my album out it makes sense for me to be there".
Adele is among those with the most nominations at this year's Brit Awards after being nominated for four trophies.


Labour's deputy leader has warned Digital Minister Matt Hancock to avoid any conflict of interests in his future dealings with ex-chancellor George Osborne, now Evening Standard editor.

Tom Watson said Mr Osborne would be expected to seek to influence ministers on media policy in his new role, and urged Mr Hancock to excuse himself from any matters relating to the Standard.
Mr Osborne has faced calls to quit as an MP after he accepted the editorship.
But he insists he can do both jobs.
In a letter to the minister of state for digital and culture, Mr Watson pointed to the long-standing personal and professional relationship Mr Hancock had enjoyed with Mr Osborne.
"It is a matter of public record that your first job in politics, in 2005, was as an economic advisor to Mr Osborne, who was then the shadow chancellor," he wrote.
"You later became Mr Osborne's chief of staff. These roles and the contacts you will have made through holding them, were no doubt helpful to you as you successfully sought selection as Conservative parliamentary candidate for West Suffolk, the constituency you have represented as an MP since 2010."
Mr Watson stressed that there was "no secret, and no shame, in a Conservative MP being a loyal ally of his former boss and powerful patron" - but he warned that as a minister he will now have responsibility for policy areas in which Mr Osborne and his new employer have a commercial interest.
Politics and journalism
He argued that, as the Standard's editor, Mr Osborne "can be expected to seek to influence ministers on media policy in line with his views and the views of his paper's proprietor Mr Alexander Lebedev, both in the pages of the newspaper and in meetings with ministers.
"You would be one of the chief targets of any such attempts to influence media policy," he said.
"Your long-standing relationship with Mr Osborne means that any ministerial decisions you make from now on which affect media policy will be subject to accusations of a conflict of interest which it will be difficult for you to disprove."
Mr Osborne's new job has caused controversy after he said he intends to combine the editorship role with that of representing his Cheshire constituency of Tatton - 190 miles from the capital.
But in an open letter to his constituents, Mr Osborne said: "There is a long tradition of politics and journalism mixing. One of the greatest newspaper editors ever, CP Scott, combined editing the Manchester Guardian with being an MP.
"In our age, politicians from Iain Macleod and Richard Crossman to, of course, Boris Johnson have combined the role of editor and Member of Parliament," the Knutsford Guardian reported.


All photographs taken by Sophie Wedgwood.

Walking behind the tall, concrete tower blocks of Brixton's Loughborough Estate there's an unlikely sight. Against a backdrop of railway arches, young people trot around the floodlit manege of the Ebony Horse Club, an organisation founded in 2006 to teach equestrian skills to local children.
In this inner city neighbourhood, some children battle with a plethora of problems at both home and school, leading to truancy, high rates of teenage pregnancy, self harm and homelessness.
These issues are epitomised by the murder of Nathan Foster - a member of the club - who was shot in gang-related activity just a year after it was founded.
The organisation intends to be a safe haven away from these problems, mentoring children through a mix of sessions with youth workers, as well as helping them get into colleges and employment using their newfound equestrian skills.
One member who benefited in this way is Natasha, who is now studying equine performance and business management at Writtle College, a partner of the University of Essex.
She first came to the club when her confidence was at a low ebb.
"If Ebony wasn't there for me, then I certainly wouldn't be in halls at university," said Natasha.
"I don't know if I would have ever gone through any sort of higher education, since I didn't believe I had the confidence to study away from home."
As well as building confidence and teaching a practical skill, working with the horses teaches the children responsibility as, in addition to riding them, they must groom and care for the steeds.
Linda Hinds, the operations manager of the stables, also believes that due to the size of the horses, the children are made to think about their actions, giving many of them their first positive contact with an animal.
Nahshon is one of Ebony's oldest members, having started to ride at the age of nine.
Having overcome a lot, he now works at Trent Park Equestrian Centre in North London.
"Learning to ride kept me out of trouble, and being at Ebony definitely helped me become a better and more independent person," he said.
"I was encouraged to step up and take control of my life.
"Without it, my life would be very different, and I would probably would have been in prison.
"In the future, I always want to be around horses."
With membership numbers having grown from five to 79 over the past decade, about 140 young people now visit the centre every week.
The waiting list is more than a year long, but priority is given to children from the immediate area, alongside referrals from social services and doctors, such as one young man with attention deficit hyperactivity disorder (ADHD).
Lynden, 14, who has been riding for the past five years, said: "Ebony Horse Club pushes me to be more, and gives me time and space to let go of what's happening in the outside world."


More than half of academies in England have lacked enough income to cover their annual expenditure, according to figures revealed by ministers.

An answer to a Parliamentary question shows that the proportion of academy trusts with an annual shortfall doubled in two years.
It comes amid growing warnings about school funding shortages.
But Schools Minister Nick Gibb told MPs on Tuesday that school funding had been protected and was at record levels.
The figures have been revealed in response to a question about academy expenditure from the Liberal Democrat peer Lord Storey.
These figures for 2014-15 show that 53% of stand-alone academies were recorded as having "spent more than their income per year", up from 42% in the previous year.
Among multi-academy trusts, the proportion spending more than their income was 53%, compared with 25% in the previous year.
This did not necessarily mean that the academies were left in deficit - as they could have been using reserves from previous years.
The ministerial answer says that in 2014-15 only 4% of academy trusts had such a "cumulative deficit".
But the Liberal Democrats say that it shows a rising problem with inadequate funding, for academies as well as local authority schools.
"Academies are already falling short of cash and this a deep concern to staff and parents. It shows that the system that the Conservatives have created has a shaky foundation," said Liberal Democrat education spokesman John Pugh.
"The government want to pretend that academies and free schools are the answer to the funding problems but this shows that they're not immune to the impact of the government slashing education budgets," he said.
School leaders have been increasingly vocal in concerns about funding levels.
Head teachers have been warning about having to cut school hours, governors have threatened to refuse to sign off budgets and grammar school leaders have said they might have to start charging parents.
Last week, heads were angered when it was revealed that Â£384m earmarked for converting schools into academies last year had been taken back by the Treasury.
On Tuesday, Nick Gibb, minister for school standards, faced questions from the education select committee on school funding.
He rejected suggestions of underfunding for schools and told MPs that the government had "protected funding at a time when we are dealing with an historic budget deficit".
Mr Gibb said schools were receiving more than ever before - and that this would rise with a further increase in the school population.
The way that school funding is shared out to individual schools is also being changed - with the launch of a new funding formula.
The schools minister said that the government had "grasped the nettle" on needing to reform a funding system that was often uneven and unfair.
But there was no "silver bullet" on school funding, he said, and switching to a new formula would mean winners and losers.
A Department for Education spokeswoman said these figures were about income and expenditure within the year - rather than overall deficits.
"An academy trust is required by law to balance its budget from each academic financial year to the next," said the DFE spokeswoman.
"Where the board of an academy is proposing to set a deficit budget for the current financial year, it must notify the Education Funding Agency (EFA).
"Wherever appropriate, the EFA will provide support to academy trusts experiencing financial difficulty but where we find financial mismanagement or irregularities we will not hesitate to take swift action."


TV crime drama Shetland was one of the big winners at the Scottish Baftas.

Douglas Henshall won the television actor award and the show clinched the TV drama category.
Producer Rebecca O'Brien, writer Paul Laverty and Ken Loach - filmmakers behind hits like Sweet 16, The Angels' Share and My Name Is Joe - received an outstanding contribution award.
A BBC Scotland investigation Britain's Puppy Dealers Exposed won the current affairs category.
Edith Bowman hosted the event, held at Glasgow's Radisson Blu hotel, with James McAvoy and Bill Paterson among the stars handing out awards.
Shetland -  an ITV Studios production for BBC Scotland based on the Ann Cleeves novels -  was nominated in four categories.
Douglas Henshall won the best TV actor award, beating off strong competition from Outlander star Sam Heughan and Peter Capaldi who was also nominated for his Dr Who performances.
Heughan's Outlander co-star Caitriona Balfe triumphed over Ashley Jensen and Annie Wallace to win the TV actress prize, delighting the many Outlander fans who had gathered outside the venue.
Peter Mullan received the film actor award for his role in Hector, while Couple In A Hole's Kate Dickie won this year's film actress award.
Sitcom Mrs Brown's Boys won the Comedy/Entertainment category for the second year in a row, beating off competition from Scot Squad and Two Doors Down.
Britain's Puppy Dealers Exposed, a BBC Scotland investigation by Samantha Poling, Sandeep Gill  and Liam McDougall, was honoured in the current affairs category.
The award for best single TV documentary went to  Dunblane, Our Story, an STV production for the BBC.
Martin Compston, who shot to fame after he was picked from obscurity to play the lead role in the Ken Loach film Sweet 16, presented the outstanding achievement to film award to screenwriter Paul Laverty and producer Rebecca O'Brien for their work with Sixteen Films.
"I owe my entire career to Ken, Rebecca and Paul," Compston said.
"Apart from being possibly the most important film makers Britain has ever had, they're just three lovely people who have taken a chance on people like myself and they deserve to be honoured in this way."
Hair and make-up artist Christine Gant's work in the industry over 35 years was also recognised with an outstanding contribution award.
Bafta Scotland director Jude MacLaverty said: "This has been another incredible year for Scotland's film, television and gaming industries and we're honoured to be celebrating this tremendous mix of talent tonight.
"Once again, we offer our warmest congratulations to all our worthy winners."
The winners at Bafta Scotland 2016
Actor Film - Peter Mullan, Hector
Actor Television - Douglas Henshall, Shetland
Actress Film - Kate Dickie, Couple in a Hole
Actress Television - Caitriona Balfe, Outlander
Animation - No Place Like Home, Cat Bruce, Neil Jack - KoLik
Children's Programme - All Over The Workplace, BBC Scotland/CBBC
Comedy/Entertainment - Mrs Brown's Boys 2015 Christmas special
Current Affairs - BBC Scotland Investigates: Britain's Puppy Dealers Exposed, Liam McDougall, Samantha Poling, Sandeep Gill
Director Film/Television - Douglas Mackinnon, Sherlock, The Abominable Bride
Factual Series - This Farming Life, BBC Studios/BBC Two
Feature Film - Tommy's Honour, Gutta Percha Productions, SellOutPictures
Features/Factual Entertainment - Supershoppers, Firecrest Films/Channel 4
Game - Glitchspace, Space Budgie
Short Film - Isabella, Ross Hogg, Duncan Cowles
Single Documentary - Dunblane: Our Story, STV Productions/Berriff McGinty Films/BBC One
Specialist Factual - Imagine... Richard Flanagan: Life After Death, BBC Studios/BBC One
Television Drama - Shetland, ITV Studios/BBC One
Writer Film/Television - DC Moore, Not Safe for Work
Outstanding Contribution to Craft - Christine Cant
Outstanding Contribution to Film - Sixteen Films, Ken Loach, Rebecca O'Brien, Paul Laverty


The death of a 28-year-old man after being detained in the street is being investigated by the police watchdog.

Officers were called to Preston Close at Llantrisant, Rhondda Cynon Taff, at 01:25 BST on 24 June, to reports Jon James was shouting for help and behaving erratically.
He lost consciousness as officers tried to restrain him and died at the Royal Glamorgan Hospital on 27 June.
The Independent Police Complaints Commission has appealed for witnesses.
The coroner has been informed and a post mortem examination has been carried out.
IPCC investigators have visited the scene and spoken to neighbours to gather witness statements, including accounts from the South Wales Police officers involved.
No officers are currently under investigation but the IPCC said this would be "kept under review".