Northern Ireland needs to act now to prepare for the effects of climate change, a senior government adviser has warned.

Lord Krebs sits on an independent panel which advises central government and the devolved administrations on greenhouse gas emissions.
Agriculture is the biggest emitter of greenhouse gases in Northern Ireland, accounting for 29%.
He said flooding was the biggest risk, with about 60,000 homes vulnerable.
Lord Krebs, who was in Belfast to present a report on the specific challenges for Northern Ireland, said increased rainfall could also pose a risk to agriculture from soil erosion.
If properly managed, however, climate change could present opportunities, with warmer summers and longer growing seasons, he added.
Agriculture, power generation and transport are the biggest emitters here.
There have been calls for local climate change legislation; Northern Ireland is the only devolved administration not to have it.
It would mean targets for cuts to greenhouse gas emissions.
But there has been opposition to that, with claims it could make industry and farming here less competitive.
Lord Krebs said climate change could no longer be denied and there was now "absolutely overwhelming scientific consensus" about it.
DUP MP Sammy Wilson said the assembly should not pander "to mostly well off green zealots" by introducing a "disastrous" policy.
Agriculture and Environment Minister Michelle McIlveen has said she would keep the issue of local legislation "under review".


Charlton striker Yaya Sanogo should be "banned for the rest of the season" for his "disgusting" red card against MK Dons, says Dons boss Karl Robinson.

Sanogo, on loan from Arsenal, was sent off during injury-time of the 0-0 draw for appearing to elbow Dons defender Antony Kay off the ball.
"He's clearly off the ball, he's had one go and a second," said Robinson.
"Equally, Rob Hall's been clotheslined on the the far side. Some of the challenges were borderline assault."
He continued to BBC Three Counties Radio: "I was expecting to see the police in the tunnel at the end of the game because the challenges were so bad.
"I know it's about fighting and competing for survival in one of the most difficult leagues in Europe, but there's still got to be an element of control."
Addicks boss Jose Riga said after the game: "[I've] not yet [seen the Sanogo incident], but he did something silly - apologised - so I suppose he did something.
"We don't need this in our situation, certainly not.
"We are all nervous about the situation. [To not win] against a direct opponent, it's two times more difficult [to survive]."
In 2012, Dons defender Gary MacKenzie headbutted Charlton striker Yann Kermorgant at The Valley, an action for which he apologised for afterwards.
"Four years ago I sent Gary MacKenzie into the press conference to apologise to everybody for his actions," said Robinson.
"We took full responsibility and it's not an acceptable part of the game, and today it's been the reverse happened against us - he could have broken his jaw.
"Their manager didn't shake my hand until we were in the tunnel either, so it ended on a bitter note for me. But we were the better team."
The result at The Valley leaves the Dons 21st in the Championship with 10 games to play, and seven points above Charlton in 23rd.


A cyclone warning for Australia's Northern Territory has been cancelled.

Australia's Bureau of Meteorology had forecast a tropical storm north of Darwin to intensify into a cyclone on Tuesday.
Authorities said although conditions had improved, heavy rainfall was still likely to cause a flood risk to some communities.
It comes after a cyclone hit Australia two weeks ago, bringing flooding that killed at least six people.
Northern Territory authorities have warned people to avoid flooded roads.
"The system looks unlikely to reach cyclone intensity until it moves further west into the Timor Sea," said forecaster Adam Morgan.
If the weather system does intensify, it will be named Cyclone Frances.


The quest to find the most mysterious particles in the Universe is entering a critical phase, scientists say.

An experiment located in the bottom of a gold mine in South Dakota, US, could offer the best chance yet of detecting dark matter.
Scientists believe this substance makes up more than a quarter of the cosmos, yet no-one has ever seen it directly.
Early results from this detector, which is called LUX, confirmed it was the most powerful experiment of its kind.
In the coming weeks, it will begin a 300-day-long run that could provide the first direct evidence of these enigmatic particles.
Spotting WIMPs
Beneath the snow-covered Black Hills of South Dakota, a cage rattles and creaks as it begins to descend into the darkness.
For more than 100 years, this was the daily commute for the Homestake miners searching for gold buried deep in the rocks.
Today, the subterranean caverns and tunnels have been transformed into a high-tech physics laboratory.
Scientists now make the 1.5km (1-mile) journey underground in an attempt to solve one of the biggest mysteries in science.
"We've moved into the 21st Century, and we still do not know what most of the matter in the Universe is made of," says Prof Rick Gaitskell, from Brown University in Rhode Island, one of the principle investigators on Large Underground Xenon (LUX) experiment.
Scientists believe all of the matter we can see - planets, stars, dust and so on - only makes up a tiny fraction of what is actually out there.
They say about 85% of the matter in the Universe is actually dark matter, so called because it cannot be seen directly and nobody really knows what it is.
This has not stopped physicists coming up with ideas though. And the most widely supported theory is that dark matter takes the form of Weakly Interacting Massive Particles, or WIMPs.
Prof Gaitskell explains: "If one considers the Big Bang, 14bn years ago, the Universe was very much hotter than it is today and created an enormous number of particles.
"The hypothesis we are working with at the moment is that a WIMP was the relic left-over from the Big Bang, and in fact dominates over the regular material you and I are made of."
The presence of dark matter was first inferred because of its effect on galaxies like our own.
As these celestial systems rotate around their dense centre, all of the regular matter that they contain does not have enough mass to account for the gravity needed to hold everything together.  Really, a spinning galaxy should fly apart.
Instead, scientists believe that dark matter provides the extra mass, and therefore gravity, needed to hold a galaxy together.
It is so pervasive throughout the Universe that researchers believe a vast number of WIMPs are streaming through the Earth every single second. Almost all pass through without a trace.
However, on very rare occasions, it is thought that dark matter particles do bump into regular matter - and it is this weak interaction that scientists are hoping to see.
The LUX detector is one of a number of physics experiments based in the Sanford Underground Research Facility that require a "cosmic quietness".
Prof Gaitskell says: "The purpose of the mile of rock above is to deal with cosmic rays. These are high-energy particles generated from outside our Solar System and also by the Sun itself, and these are very penetrating.
"If we don't put a mile of rock between us and space, we wouldn't be able to do this experiment."
Inside a cavern in the mine, the detector is situated inside a stainless steel tank that is two storeys high.
This is filled with about 300,000 litres (70,000 gallons) of ultra-purified water, which means it is free from traces of naturally occurring radioactive elements that could also interfere with the results.
"With LUX, we've worked extremely hard to make this the quietest verified place in the world," says Prof Gaitskell.
At the detector's heart is 370kg (815lb) of liquid xenon. This element has the unusual, but very useful, property of throwing out a flash of light when particles bump into it.
And detecting a series of these bright sparks could mean that dark matter has been found.
The LUX detector was first turned on last year for a 90-day test run. No dark matter was seen, but the results concluded that it was the most sensitive experiment of its kind.
Now, when the experiment is run for 300 days, Prof Gaitskell says these interactions might be detected once a month or every few months.
The team would have to see a significant number of interactions -  between five and 10 - to suggest that dark matter has really been glimpsed. The more that are seen, the more statistical confidence there will be.
However, LUX is not the only experiment setting its sights on dark matter.
With the Large Hadron Collider, scientists are attempting to create dark matter as they smash particles together, and in space, telescopes are searching for the debris left behind as dark matter particles crash into each other.
Mike Headley, director of the South Dakota Science and Technology Authority, which runs the Sanford laboratory, says a Nobel prize will very probably be in store for the scientists who first detect dark matter.
He says: "There are a handful of experiments located at different underground laboratories around the world that want to be the first ones to stand up and say 'we have discovered it', and so it is very competitive."
Finding dark matter would transform our understanding of the Universe, and usher in a new era in fundamental physics.
However, there is also a chance that it might not be spotted - and the theory of dark matter is wrong.
Dr Jim Dobson, based at the UK's University of Edinburgh and affiliated with University College London, says: "We are going into unknown territory. We really don't know what we're going to find.
"If we search with this experiment and then the next experiment, LUX Zeppelin, which is this much, much bigger version of LUX - if we didn't find anything then there would be a good chance it didn't exist.
He adds: "In some ways, showing that there was no dark matter would be a more interesting result than if there was. But, personally, I would rather we found some."
Prof Carlos Frenk, a cosmologist from Durham University, says that many scientists have gambled decades of research on finding dark matter.
He adds: "If I was a betting man, I think LUX is the frontrunner. It has the sensitivity we need.  Now, we just need the data.
"If they don't [find it], it means the dark matter is not what we think it is. It would mean I have wasted my whole scientific career - everything I have done is based on the hypothesis that the Universe is made of dark matter. It would mean we had better look for something else."
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The Israeli military says its aircraft and tanks attacked targets in the Gaza Strip overnight in response to rocket fire by Palestinian militants.

Palestinian officials said two people were hurt as sites belonging to Hamas, Islamic Jihad and the Popular Front for the Liberation of Palestine were hit.
Shells also reportedly damaged a water tower in the town of Beit Hanoun.
Earlier, a rocket launched in Gaza landed near a house in the Israeli town of Sderot without causing any injuries.
Israel and militants in Gaza led by Hamas, which dominates the coastal territory, fought a 50-day war in the summer of 2014.
Since then, a ceasefire has largely held, but some small jihadist groups have defied the agreement and periodically fired rockets at Israel.
A senior Israeli military official told the Haaretz newspaper that "dozens" of strikes on Sunday night had targeted Hamas "infrastructure".
"The attacks were out of the ordinary, but there is no intention to escalate the situation," the official added.
Military spokesman Lt Col Peter Lerner said it remained "committed to the stability of the region and operated in order to bring quiet to the people of southern Israel".
Hamas spokesman Sami Abu Zuhri said: "We hold [Israel] responsible for the escalation in the Gaza Strip and we stress that its aggression will not succeed in breaking the will of our people and dictate terms to the resistance."
Hamas leader Mahmoud al-Zahhar later blamed "a group not committed to the principles of the resistance of the occupation" for firing the rocket at Sderot.
Haaretz identified the group as Ahfad al-Sahaba-Aknaf Bayt al-Maqdis, which it said was affiliated with Salafist groups that identify with so-called Islamic State (IS).


Footage of a prototype superfast drone being developed by Sony has been posted online.

25 August 2015 Last updated at 18:32 BST
A test flight by Aerosense - a joint-venture created by Sony and the robotics firm ZMP - shows the plane-shaped drone taking off vertically.
The firm says it can reach a top speed of 106mph (170km/h), more than twice as fast as other commercial drones.
It is designed to carry objects and could be used in industrial applications as soon as next year.
But one expert has raised safety concerns.


The head of Northern Ireland's Education Authority (EA) has warned that it is facing "very real pressures" due to a £22m reduction in its budget.

The EA delivers and funds things like school transport, meals and support for special educational needs.
It also provides other services like educational psychology and welfare.
In a letter, sent to school principals, EA's chief executive Gavin Boyd warns that the body will have to make "difficult decisions".
"I recognise the difficulties this creates for schools but you will appreciate the very real pressures for the authority as demand for services continues to increase," Mr Boyd's letter said.
"We are at the beginning of a journey of transformation."
The authority's budget had previously been reduced from £405m in 2014/15 to approximately £396m in 2015/16.
Some school principals have expressed concern that frontline services could be at risk due to the reductions.
The principal of Seaview Primary School in Belfast, Corinne Latham, said that they relied on EA to provide help for many of its 440 pupils.
"Some of our children have very acute needs, and it is our responsibility under law to provide for those needs," she said.
"This is absolutely appalling because some of the ground services we receive from the EA are just not there already.
"We have some children who are not attending school as often as they should.
"I have had to get in touch with the Education Welfare officer for this area, and he doesn't have the people on the ground to support those children.
"I think children in Northern Ireland are going to face the worst of these cuts, and unfortunately their rights are being totally ignored."
Recently, groups representing the leaders of 80 large schools warned schools would see larger class sizes, fewer teachers and be able to offer fewer subjects due to rising costs.
This had led to a number of principals writing to directly to parents of pupils outlining the situation in their school.
Kevin Donaghy, principal of St Colman's Primary in Annaclone, County Down, sent a letter to parents stating that his school is facing a £41,000 rise in salary costs.
"Parents need to be aware that there are challenging decisions that we as principals have to take," he said.
"They need to be asking political representatives what they are going to do to help children.
"The various political parties say they want a first-class education system. The only way we can get a first-class system is to actually fund it properly," he added.


The population of Wales has risen by 5% to 3.1m from 2001 to 2011, figures from the latest census have shown.

The increase is the largest seen in any census period since 1951, with migration given as the main factor.
While 73% of the population was born in Wales, 5% were born outside the UK, up from 1% in 2001.
The number of English-born people in Wales has also risen slightly over the past decade to 21%.
A total of 93,600 people born overseas moved to Wales between 2001 and 2011. However Pete Stokes, statistical design manager with the Office of National Statistics, said most "foreigners" in Wales were born in England.
He explained: "Out of a group of 20 people, 15 would be born in Wales, four in England and one elsewhere in the world."
He said the ethnic mix had not changed much since the previous survey. Wales is the least ethnically diverse area among the areas covered by the census, which also includes the English regions with 93% classing themselves as white, down from 96% in 2001.
Cardiff is the only local authority area where more than 10% of the population were born outside the UK. It also has the highest proportion of ethnic minority people at 20%.
A total of 1.36% of people living in Cardiff were born in India. Throughout Wales, 2.2% of people were of Asian origin, 0.6% of African, Caribbean or other black heritage and 1% of mixed ethnic origin.
Over 67,000 were from other EU countries including 12,000 from Ireland, and over 100,000 were from other parts of the world including Australia, New Zealand and South Africa.
There were more women at 1.6m, against 1.5m men.
Nearly one in five, or 563,000 people, were over the age of 65, a higher proportion than in England.
All areas of the country saw population growth except for Blaenau Gwent, which is also the county where most Welsh-born people live.
Glen Watson, director general of the ONS said: "It points to a growing picture of diversity and change in Wales."


Holyrood ministers are considering scrapping the use of the word "benefits" when they take charge of parts of the social security system.

Responsibility for ill health and disability benefits is being devolved to Holyrood.
Social Security Minister Jeane Freeman believes there is "value in looking at at whether we continue to use the word 'benefits'" when that happens.
A consultation on how devolved benefits should be delivered has been launched.
Ms Freeman, who was elected to Holyrood in May, made the comments as she launched the 13 week consultation with Social Security Secretary Angela Constance.
The Scottish government has already made clear its ambition to place "dignity, fairness and respect" at the heart of the new welfare system.
Ms Freeman said: "I do think there is value in looking at whether or not we continue to use the word 'benefit', because there is an implication in there that is the rest of us doing something nice for somebody else, when actually what we have said consistently as a government is that social security is an investment we make collectively in ourselves.
"Part of how you make dignity, fairness and respect real as opposed to just fine words is about the culture that the organisation that will deliver those benefits embraces, and how people receive that in their dealings with that organisation.
"There are some things you can do to affect quite quick cultural change, and part of that is around language and thinking, so there is value in looking at whether or not we don't simply call these payments, as opposed to benefits, or some other word."
A social security bill is expected to be introduced to Holyrood in May or June next year, while the proposed new Scottish social security agency could be making payments to people before the 2021 elections.
Payments such as disability living allowance, personal independence payments, attendance allowance, severe disablement allowance and industrial injuries disabled benefit will become the responsibility of MSPs, as well as carer's allowance - which the Scottish government has already committed to increasing to the same level as jobseeker's allowance.
Other benefits being devolved include sure start maternity grants - which are to be changed to best start grants -  funeral payments, cold weather and winter fuel payments, discretionary housing payments and some powers over Universal Credit.
Westminster will retain responsibility for much of the Universal Credit system, along with pensions, child benefit and maternity and paternity pay.
Ms Constance described Holyrood taking responsibility for part of the existing welfare system as "the biggest and most complex programme of change, probably in the history of devolution".
She added: "We want to gather views from as many people as possible from across Scotland about their own experience of benefits and how they think the system could be improved in the future."
Scottish Labour social security spokesman Mark Griffin said: "The new powers coming to our Scottish Parliament give us the opportunity to build a Scottish welfare state with dignity at its heart.
"We can do things differently now. With the power to top up and create new benefits, there is a huge opportunity to tackle poverty and inequality in Scotland.
"Labour will support the government where they show ambition in social security but we will not allow the SNP to simply pass on Tory cuts."


A punter in Aberdeen has placed a bet of £50,000 on Andy Murray to win Wimbledon.

The wager on Murray - the competition's 5/2 second favourite, behind Novak Djokovic - would net a £175,000 return, including the stake.
Ladbrokes believes it to be the largest tennis bet ever placed in Scotland.
The company's Alex Donohue said: "Our Murray fan in Aberdeen has given his hero the ultimate vote of confidence with this record-breaking bet."
Murray ended Britain's 77-year wait for a men's singles champion in 2013 when he beat Djokovic in the final.
The British number one is due to get his campaign under way against Mikhail Kukushkin of Kazakhstan on Tuesday.


Alexandre Pato scored on his Chelsea debut as Aston Villa continued their slide towards relegation.

The home fans chanted against their players and owner Randy Lerner as the Blues took control in the second half.
Ruben Loftus-Cheek's deflected shot and Pato's precise penalty had given the visitors a healthy half-time lead.
Pedro scored twice - slotting in Oscar's pull-back and hammering home a loose ball - before Alan Hutton was sent off to compound Villa's misery.
Aston Villa's Premier League survival may still be possible in theory but, with 15 points separating them from safety and six games left, attention has long since switched to the longer term in the Holte End after seven straight league defeats.
Before kick-off, fans held aloft banners asking "Proud History, What future?" as they contemplate a Championship campaign on the pitch and owner Randy Lerner's continuing attempts to sell up off it.
Their protests increased in volume towards the end of the match with substitute Leandro Bacuna - who spoke of his plans to leave the club this week - picked out for particular criticism and a synchronised show of discontent on the 74th minute.
The final whistle was greeted with resounding boos from the fans who remained in a fast-emptying Villa Park.
Their team - without Gabriel Agbonlahor after photos were published of the striker apparently smoking on a holiday in Dubai - initially worked hard to provide some short-term solace for their fans.
With Eric Black in charge following Remi Garde's departure on Tuesday, there was more industry and invention in attack in the first half with Jordan Ayew and Carles Gil both going close.
But, as has been the case so often this season, their efforts were fatally undermined by a brittle defence as Aly Cissokho allowed Cesar Azpilicueta too much space down the left to create the opener and then bundled into Pato to give away the spot-kick for the second.
Jack Grealish was greeted warmly as he returned from injury as a substitute and Alan Hutton was applauded off despite being shown a second yellow card for a heavy challenge on Loftus-Cheek.
But, after an insipid second-half surrender, there was little love for the rest of Villa's team as they trooped off.
It was difficult to measure Chelsea against opposition in such disarray, but some of the fringe squad members shone in a win that extended their unbeaten league run to 15-straight games.
Pato said after the match that he was "surprised" to be brought on after Loic Remy suffered a slight injury, but showed some nice touches. In defence, fellow debutant Matt Miazga coped well with the aerial threat from Rudy Gestede while a hungry Loftus-Cheek curled a shot just wide as he hunted his second.
Pedro was particularly bright and could have had a hat-trick had a deft chip not been ruled out in the first half for a marginal offside.
With matches against Tottenham and Leicester to come in May, Chelsea will have a say in the climax to this season's title race. With Italian Antonio Conte reportedly lined up for the manager's job, they may be more directly involved next season.
Caretaker Aston Villa boss Eric Black: "I'm not overly delighted losing 4-0 today, but things obviously run a little deeper.
Media playback is not supported on this device
"If you're bottom of the league and have won three games all season, you're not going to be flying high. We have to be professional until the end, and do our utmost for the club and supporters. We need to continue to work hard to get this club back to where it should be.
"We have got to win back the fans and it will happen. How quickly, I don't know. We have only won two games at home and there can be a disconnect, but we carry on and try and change their minds."
Chelsea boss Guus Hiddink on BT Sport on Alexandre Pato's debut wait: "He was counting down the days, and knocking on the door. I could have brought him on after 14 days or three weeks but it would have been irresponsible.
Media playback is not supported on this device
"He was not strong enough to battle in the league. He has to deal with the competition but he finally stepped up."
Aston Villa play Bournemouth at Villa Park next Saturday. Chelsea are away to Swansea on the same day.
Match ends, Aston Villa 0, Chelsea 4.
Second Half ends, Aston Villa 0, Chelsea 4.
Corner,  Aston Villa. Conceded by Matt Miazga.
Attempt missed. Jack Grealish (Aston Villa) right footed shot from the left side of the box is close, but misses to the left. Assisted by Jordan Ayew with a cross.
Ashley Westwood (Aston Villa) is shown the yellow card for a bad foul.
Baba Rahman (Chelsea) wins a free kick on the left wing.
Foul by Ashley Westwood (Aston Villa).
Second yellow card to Alan Hutton (Aston Villa) for a bad foul.
Ruben Loftus-Cheek (Chelsea) wins a free kick on the left wing.
Foul by Alan Hutton (Aston Villa).
Attempt missed. Baba Rahman (Chelsea) left footed shot from the centre of the box is close, but misses to the left. Assisted by Oscar with a through ball.
Substitution, Aston Villa. Jordan Lyden replaces Idrissa Gueye.
Attempt saved. Branislav Ivanovic (Chelsea) right footed shot from outside the box is saved in the bottom left corner.
Alan Hutton (Aston Villa) is shown the yellow card for a bad foul.
Alexandre Pato (Chelsea) wins a free kick in the attacking half.
Foul by Alan Hutton (Aston Villa).
Offside, Chelsea. Cesc Fàbregas tries a through ball, but Baba Rahman is caught offside.
Substitution, Chelsea. Jake Clarke-Salter replaces Pedro.
Corner,  Aston Villa. Conceded by César Azpilicueta.
Attempt missed. Ashley Westwood (Aston Villa) right footed shot from outside the box is close, but misses to the left.
Attempt blocked. Jordan Ayew (Aston Villa) left footed shot from the centre of the box is blocked. Assisted by Alan Hutton.
Attempt blocked. Ashley Westwood (Aston Villa) right footed shot from outside the box is blocked. Assisted by Jack Grealish.
Corner,  Aston Villa. Conceded by César Azpilicueta.
Substitution, Aston Villa. Leandro Bacuna replaces Carlos Sánchez.
Substitution, Aston Villa. Jack Grealish replaces Carles Gil.
Carlos Sánchez (Aston Villa) is shown the yellow card for a bad foul.
Ruben Loftus-Cheek (Chelsea) wins a free kick in the attacking half.
Foul by Carlos Sánchez (Aston Villa).
Ruben Loftus-Cheek (Chelsea) wins a free kick in the attacking half.
Foul by Carlos Sánchez (Aston Villa).
Goal!  Aston Villa 0, Chelsea 4. Pedro (Chelsea) right footed shot from the right side of the six yard box to the centre of the goal.
Attempt saved. Alexandre Pato (Chelsea) right footed shot from outside the box is saved in the bottom right corner. Assisted by Oscar.
Oscar (Chelsea) wins a free kick in the defensive half.
Foul by Alan Hutton (Aston Villa).
Corner,  Aston Villa. Conceded by Baba Rahman.
Foul by Ruben Loftus-Cheek (Chelsea).
Carles Gil (Aston Villa) wins a free kick on the left wing.
Corner,  Aston Villa. Conceded by César Azpilicueta.
Foul by Pedro (Chelsea).
Idrissa Gueye (Aston Villa) wins a free kick in the defensive half.


Discount supermarkets Aldi and Lidl have seen their joint share of the groceries market double to 10% in just three years, industry figures show.

Analysts Kantar Worldpanel said Aldi's market share was 5.6% in the 12 weeks to 8 November, while Lidl's was 4.4%.
Sainsbury's was the only one of the "big four" supermarket chains to increase sales and market share.
As a result, Kantar said Sainsbury's had overtaken Asda to become the second-largest UK supermarket chain.
Tesco remains the UK's largest supermarket with a 27.9% market share, while Sainsbury's has 16.6%, with Asda on 16.4%.
Asda's sales fell 3.5% in the latest quarter from a year earlier, more than any of its main rivals.
The figures come ahead of the release of Asda's third-quarter results. Asda chief executive Andy Clarke had described the 4.7% fall in the supermarket's sales in the previous quarter as the firm's "nadir".
Source: Kantar Worldpanel (12 weeks to 8 November 2015)
The discount chains have been gradually eating into the market share of the biggest supermarkets, and have provoked a fierce price battle among the top four chains.
The latest Kantor Worldpanel figures show Aldi's sales rose 16.5% in the latest quarter from a year earlier, while Lidl's increased by 19%.
In contrast, sales at Tesco, the UK's largest supermarket chain, fell 2.5% from a year earlier, while Morrisons dropped 1.7%.
Fraser McKevitt, head of retail and consumer insight at Kantar Worldpanel, said: "If you look back as recently as 2012 Aldi and Lidl only held a 5% share of the market, and it had previously taken them nine years to double their combined share from 2.5%.
"In the last 12 weeks, the two retailers have attracted another additional million shoppers compared with last year, while average spend per trip has increased by 4% to Â£18.85, which is 78p ahead of the total retailer average.
"The discounters show no sign of stopping and with plans to open hundreds of stores between them, they'll noticeably widen their reach to the British population."
Elsewhere, Waitrose and the Co-operative saw sales rise by 2.7% and 1.5% respectively.
The Co-operative's market share grew to 6.3% from 6.2% - its first year-on-year share gain since 2011, when the benefits of its acquisition of the Somerfield chain were still being felt.


Australia were bowled out for only 85 on the first day of the second Test against South Africa at Hobart.

On a green surface and in damp, overcast conditions, Australia fell to 8-4 and 17-5 after losing the toss.
Vernon Philander took 5-21, Kyle Abbott 3-41 and though Steve Smith ended 48 not out, Australia slumped to their lowest home total against the Proteas.
South Africa reached 171-5 by the close for a lead of 86 - Hashim Amla hitting 47, while Mitchell Starc has 3-49.
The tourists, without injured skipper AB de Villiers and pace spearhead Dale Steyn, already lead the three-Test series 1-0.
This Test is the first time since both made their debuts against England in December 2004 that South Africa have played without either of them.
In the absence of Steyn, Philander tore through the Australia top order, starting with David Warner edging a drive to a delivery so wide he could barely reach it.
Joe Burns was lbw to Abbott and, after Usman Khawaja and Adam Voges edged behind the wicket, debutant Callum Ferguson was run out by a direct hit from substitute fielder Dane Vilas for three.
From five wickets down, Australia needed captain Smith to get past their lowest home total of 58, but they were still shot out for the worst score in a Hobart Test.
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A former school bus driver, Ariel Castro, has been charged over the abduction of three women for about a decade in Cleveland, Ohio.

Police suspect Mr Castro of holding Gina DeJesus, Amanda Berry and Michelle Knight captive in a house in Seymour Avenue, Cleveland. He has been charged with kidnapping and rape.
His brothers, Pedro and Onil, were arrested along with Ariel, but police have not charged them, saying they have no reason to believe they knew about their brother's alleged crimes.
All three were taken into custody on Monday after Amanda Berry escaped from the house and alerted the police.
Born in Puerto Rico, Ariel Castro is the owner and main occupant of the house on Seymour Avenue, where the women were held.
He has owned the house, which is reportedly subject to foreclosure for non-payment of tax, since 1992.
In November last year, he was fired from his job as a school bus driver after a number of incidents, including leaving a child on the bus in 2004 and making an illegal turn with children on board in 2009.
Mr Castro, who divorced more than a decade ago, is known to have at least one son and one daughter.
His son, Ariel Anthony Castro, wrote an article about Ms DeJesus' disappearance in 2004, even interviewing her mother, whilst studying to be journalist.
On his father's arrest, the younger Mr Castro said it was "beyond comprehension".
Ariel Castro said on his Facebook page that he was the grandfather of five children, posting a congratulatory note in April to his daughter, Arlene, on the birth of her child.
Both father and daughter are believed to have had close ties to the DeJesus family, the Cleveland Plain Dealer reports.
Arlene told "America's Most Wanted" TV show in 2004 that she was the last person to see her friend and classmate Gina DeJesus.
Meanwhile, Mr Castro was spotted attending a vigil last year to mark DeJesus' disappearance.
Court records show that Mr Castro was accused in 2005 of attacking his former wife, Grimilda Figueroa.
The Cleveland Plain Dealer reported that Figueroa, who died last year, suffered multiple injuries, including broken ribs, a knocked-out tooth, and a blood clot in her brain.
Her lawyer said Mr Castro abducted his daughters several times, despite the divorce decree making no provision for his visitation.
The Associated Press also report Mr Castro was arrested in 1993 on a domestic violence charge but the case was dropped.
Police say they visited Castro's house twice in the past - once in 2000 when Mr Castro reported a fight in the street and again in 2004, after he left a child unattended on a school bus - but had never entered the residence.
The oldest of the three brothers, Pedro Castro, also lived on the west side of Cleveland.
Despite being a high-performing student, he dropped out of school in his junior year (aged 16-17), close friend Nelson Roman told the Cleveland Plain Dealer.
Pedro Castro later quit his job operating a punch press at a factory due to his heavy drinking and in recent years was receiving social security benefits, Mr Roman adds.
He spoke to reporters about Amanda Berry's disappearance in July last year when investigators dug up an empty lot in search of her body following a tip off, two streets away from Seymour Avenue.
"That's a waste of money," Pedro Castro told a local affiliate of Fox News.
The youngest of the three brothers, Onil made a living working as a handyman, Nelson Roman told the Cleveland Plain Dealer.
He was injured during his work as a labourer and for the past five years has been receiving compensation.
Mr Roman describes Onil as "much quieter than his brother Pedro", but also a heavy drinker.
None of the brothers have been married apart from Ariel, Mr Roman adds.


Police are investigating after a disabled woman's Belfast home was attacked with paint.

The incident happened in Silverstream Crescent in the north of the city on Friday morning.
It was reported to the PSNI just after 08:00 BST. The Police are treating the incident as criminal damage.
The victim lives alone and was very distressed by the incident, a relative told the BBC.


Aerospace and defence group EADS has reported a rise in profits and sales in 2012, boosted by a strong performance from its aircraft maker Airbus.

Net profit for 2012 at EADS rose 19% to 1.23bn euros ($1.61bn; Â£1.06bn). Revenues rose 15% to 56.48bn euros.
Revenues at Airbus rose 17% to 38.59bn euros, mostly due to commercial sales.
However, EADS's profit in the fourth quarter fell sharply after taking one-off charges at its helicopter and defence electronics divisions.
Net profit in the three months to December fell 47% from a year ago to 325m euros.
This was after a 198m-euro hit at its defence electronics contractor Cassidian due to restructuring costs, and a 100m-euro charge at Eurocopter after renegotiating contracts with government customers.
Looking ahead, EADS said its focus was on growing profits, adding there was "still some way to go to meet our profitability targets".
For 2013, it is targeting an operating profit of 3.5bn euros and expects to see "moderate growth" in revenues, though results will be affected by problems with its A350 XWB model.
Shares in EADS rose more than 7% in lunchtime trading in Paris.
In 2012 the group's order intake showed "continuing commercial momentum across the EADS portfolio", the firm said.
At the end of 2012, its order book had increased by 5% to 566.5bn euros.
The bulk of that came from Airbus. Its order book increased 6% to 523.4bn euros, although it took fewer orders in 2012 than the year before.
"A strong focus on deliveries helped to significantly improve cash generation during the fourth quarter," said chief executive Tom Enders in a statement.
"Going forward, the focus on bottom line growth remains our priority number one as a management team."
Last month, rival Boeing also reported a sharp rise in profits, thanks in part to stronger sales of commercial planes.
Earlier this month, Airbus said it would not use lithium-ion batteries in its forthcoming A350 plane because of problems that have grounded Boeing's 787 Dreamliner.
International regulators grounded all 787 Dreamliners in January so that safety checks could be carried out on their batteries after incidents on a Japan Airlines plane and an All Nippon Airways plane.
Investigations into the battery have so far proved inconclusive.
Airbus's A350, which was intended to challenge the Dreamliner, has been delayed because of a problem with its wings.
"The A350 XWB programme remains challenging," EADS said. "Any schedule change could lead to increasingly higher impact on provisions."
EADS also invited shareholders to an extraordinary meeting on 27 March to approve its new governance structure and a share buyback programme for up to 15% of its stock.
Last year, the group announced sweeping governance changes that will result in Germany and France eventually holding equal stakes in EADS of about 12%, and Spain holding 4%.
This followed the collapse of a proposed merger between EADS and BAE Systems after political deadlock between the UK, French and German governments.


Relegated Hull KR have signed Huddersfield Giants half-back Jamie Ellis on a season-long loan deal.

Ellis, 27, played 17 Super League games in 2016, scoring five tries.
He told the club website: "It's going to be a competitive season, but hopefully we should do really well and I'm looking to help Hull KR get back up to where they belong."
Meanwhile, Albert Kelly, Mitch Allgood, Kevin Larroyer, Josh Mantellato and John Boudebza have all been released.


A 12-seat private box in the Royal Albert Hall close to where the Queen sits when she attends events has gone on sale for £2.5m.

The seats in the Grand Tier are located five boxes away from the royal box in the Grade I listed building.
Agents Harrods Estates said it was the first time such a box had come on the market in almost a decade and there had "already been a bit of interest".
Buying the box will give the owner access to two-thirds of events.
They will also become a member of the Corporation of the Hall of Arts and Science which helps to operate the South Kensington building.
Nicholas Shaw of Harrods Estates said it was "the most expensive box we have ever offered for sale".
The box is on the western side of the auditorium and has approximately 849 years remaining on its lease.
A five-seat box situated on the second tier, whose previous owners included Earl Spencer and the Duke of Devonshire, went on sale in 2011 for £550,000.


A two-year-old girl has died and two other children were injured after car hit a wall and landed on its roof.

The car driver has been arrested on suspicion of causing death by dangerous driving following the crash near the village of Horton, Dorset, on Sunday.
Officers were called to reports of a "serious road traffic collision" on the B3078 at 21:20 BST.
A blue MG car carrying five people had left the road and collided with a wall before overturning, Dorset Police said.
The girl's next of kin have been informed and the coroner notified, police said.
An eight-year-old boy from Wimborne suffered potentially life-threatening injuries and was taken to hospital in Southampton.
An 11-year-old girl from Corfe Mullen suffered bruising and was taken to Poole Hospital for treatment
The driver of the car, a 28-year-old man from the Wimborne area, has been arrested and is currently assisting police with their enquiries.
He and a female passenger, 28, were treated for minor injuries and shock.
Police have appealed for information from anyone who saw the car prior to the crash.
The road, between Witchampton and Horton, has reopened after investigations of the scene finished.


Three children have been killed after a building collapsed at a nursery school in northern China, state media says.

The children were taken to hospital but died of their injuries, according to the official Xinhua News Agency.
Three other children were injured in the incident, in Yongqing county, in Hebei province, Xinhua added.
Safety standards of school buildings have been a public concern in China since many collapsed during a devastating earthquake in 2008.
Thousands of school children were among the almost 90,000 dead, leading to a public outcry over shoddy construction and the lack of safety measures.
Five children were killed earlier in the week in eastern China, when the wall at the side of a basketball court suddenly collapsed, officials said.


Hundreds of teachers at 60 schools across Northern Ireland are forming picket lines to protest against an "insulting" pay offer.

The lunchtime action is supported by four teaching unions, and it comes after 13 months of talks with the Education Authority ended in October.
The unions walked out over an offer of a 1% pay rise for 2016-17, and no pay rise last year.
Education Minister Peter Weir said he was "disappointed" by the action.
"We have to realise we are in tough economic circumstances in which the support needs to be for schools," he said.
The teaching unions involved are the Irish National Teachers' Organisation (INTO), the Association of Teachers and Lecturers (ATL), the Ulster Teachers' Union (UTU) and the National Association of Head Teachers (NAHT).
The schools impacted include six in County Armagh, seven in County Tyrone, 16 in County Down, eight in County Londonderry and 22 across County Antrim and Belfast.
Gerry Murphy, INTO's northern secretary, said teachers in Northern Ireland are paid 16% less than in some areas of the UK.
"It's a postcode lottery for Northern Ireland teachers," he said. "To be paid 16% less than their UK counterparts is more than disheartening."
UTU chairperson Avril Hall-Callaghan said the Scottish Parliament awarded teachers a 2.5% staged pay deal last year and the union has asked that the education minister consider a staged deal as a way forward in the dispute.
She urged Education Minister Peter Weir not to take teachers for granted.
"They have suffered for five years of all the cutbacks that there have been in the education service, they've worked in schools where maybe their colleagues have been made redundant," she said.
"They've taken up the slack, they have kept the education system running for him and I think it's now his turn to put something back for them."
Director of ATL, Mark Langhammer, said his was traditionally a "moderate teaching association" but that 51% of members backed a strike and 89% were in favour of industrial action.
"The case for decent pay for teachers is an unimpeachable case," he said.
"It is just a matter of priorities, not money."


Police forces need to improve failings in child protection, a watchdog's report has said.

Her Majesty's Inspectorate of Constabulary examined forces across England and Wales, including North Wales Police and Dyfed-Powys Police.
HMIC said it found poor practice in more than a third of cases it looked at and anticipated this would apply to all police forces.
Gwent Police and South Wales Police were not inspected.
Dyfed-Powys Police was one of the forces inspected as part of a report called In Harm's Way which said: "There is, however, a continuing rise in referrals to the police of child protection cases (most notably in respect of some elements of child sexual exploitation, such as online grooming).
"Police forces are just beginning to tackle these kinds of offending while simultaneously trying to respond to the increasing numbers of non-recent cases of abuse, which are now being reported."
Dyfed-Powys Police welcomed the report and said protecting children and vulnerable people was an "absolute priority".
"The force will now review in detail the recommendations from these recent reports published and incorporate any areas for development into existing programmes of work," it said.
The report looked at cases going back two years, including online child exploitation and how police share and cross-check information.
Any pockets of excellent practice found were said to be the result of "dedicated and professional individuals and teams, rather than a united, understood and applied focus on protecting children at force level".
The report added: "On too many occasions HMIC found that investigations into child abuse or neglect were poor and plagued by delay and the response to reports of offences against children - ranging from online grooming to domestic abuse - was inadequate.
"Considerable resources are being spent on child protection processes that do not necessarily lead to help for a child, while core police duties - for example, to undertake enquiries and investigations - are not being pursued effectively."


Manchester City Women made it three wins from three to start the Women's Super League season with a hard-fought win at Birmingham City Ladies.

City led through Daphne Corboz's tap-in after Nikita Parris hit the post.
Steph Houghton's curling free-kick towards the bottom corner was well kept out by keeper Sophie Baggaley as the visitors dominated the game.
In second-half stoppage time, Jane Ross headed home Parris' pinpoint cross to secure all three points.
Birmingham's best chance came through Melissa Lawley whose drive was saved by Karen Bardsley, but the hosts were second best throughout.


Prosecutors in Kazakhstan have opened a criminal inquiry into the use of weapons by police after 16 protesters were killed earlier this month.

The deaths occurred in clashes between police and oil protesting workers in Zhanaozen on 16 and 17 December.
A "criminal enquiry into the use of weapons by the security forces" had been opened, the prosecutor-general's office said on Thursday.
The violence was the worst since Kazakhstan's independence 20 years ago.
The investigation comes after video footage emerged on the internet appearing to show security forces beating and shooting people.
Eyewitnesses said police fired on unarmed oil workers, who had been protesting for months, in the town of 90,000.
But police say they were forced to defend themselves. A 20-day curfew is in effect until 5 January.
"General prosecutors opened a criminal enquiry into the use of weapons by the security forces which were aimed at hitting (their targets) and caused death," the prosecutors' spokesman Nurdaulet Suindikov said in a statement.
"An investigation group headed by a special prosecutor will carry out the investigation to ensure impartiality," the statement added.
The move marks the first time since the incident that Kazakh prosecutors have accused the police of firing on the protesters. Last week Kazakhstan asked the UN to help investigate the violence.
Separately, the privately-owned Interfax-Kazakhstan news agency reports that 18 people accused of taking part in the disturbances and looting have been arrested.
The governor of the Mangistau region, where the clashes occurred, has reportedly been sacked, along with the local boss of the state oil firm.
President Nursultan Nazarbayev has fired his son-in-law, Timur Kulibayev, from his position as head of Kazakhstan's sovereign wealth fund, which holds stakes in the companies whose workers were striking.
Correspondents say Mr Nazarbayev is keen to maintain his country's reputation as a bastion of stability in central Asia.


Mary Jane Veloso was due to be executed along with eight other prisoners in Indonesia on Tuesday, but was spared at the last minute.

The BBC takes a look at her story and the interventions that led to the Filipino woman's stay of execution.
She was caught in April 2010 at Yogyakarta airport in Indonesia with 2.6kg (5.7lb) of heroin. In October 2010 she was sentenced to death for drug trafficking. All her appeals were rejected.
But Veloso - 30 and a mother of two young children - has always maintained she was tricked. She said she was convinced by Maria Kristina Sergio, the daughter of one of her godparents, to travel to Indonesia to start a new job as a maid.
Veloso claims that Ms Sergio's male friends gave her new clothes and a new bag, which she was unaware had heroin sewn into it.
Ms Sergio has always denied the charges.
In a letter written to Philippine President Benigno Aquino released to the media over the weekend, Veloso said: "We're poor and I wanted to change our life but I could never commit the crime they have accused me of."
It launched two appeals to Indonesia in the two months leading up to Veloso's execution date.
In its first appeal heard in March, it argued that Veloso did not understand what was going on during her trial - an incompetent translator meant she did not even know she was being sentenced to death, it said. The appeal was rejected.
Indonesia launched its second appeal last week, arguing that Philippine police investigations showed Veloso may have been the victim of a drug syndicate.
But Indonesia dismissed that too, as it only allows one appeal for a judicial review.
Last Friday, she was sent to Nusakambangan prison island, where the executions were scheduled to be carried out.
Veloso's case drew widespread public sympathy in the Philippines, which does not have the death penalty.
Hundreds of activists held vigils outside the Indonesian embassy in Manila, and local media gave Veloso's case prominent coverage.
Her circumstances were familiar to many in the Philippines, where it is common for women to escape poverty by seeking work abroad as domestic helpers.
Veloso was scheduled to die at midnight on Tuesday.
On Monday, Mr Aquino had met President Joko Widodo on the sidelines of a regional meeting in Malaysia to discuss Veloso's case.
Philippine officials said that the next day, Mr Aquino called Indonesia's Foreign Minister Retno Marsudi and proposed keeping Veloso alive so that she could testify against drug traffickers.
Then at around 11:00 local time (06:00 BST) on Tuesday, Ms Sergio - the woman accused of duping Veloso - unexpectedly showed up at a police station in Cabanatuan city, north of Manila. She was seeking police protection saying she was receiving death threats.
At the eleventh hour, Indonesia issued a reprieve, saying Veloso was needed to testify against a "perpetrator suspected of human trafficking".
Her execution had seemed so likely that several newspapers in the Philippines went to print on Wednesday with front pages and headlines reporting it had happened.
Ms Sergio was taken to the national police headquarters north of Manila on Wednesday night.
Though no charges have been brought against her, police are investigating allegations of trafficking, illegal recruitment and fraud,
She has also maintained her innocence, saying she was only helping Veloso look for a job.
Mary Jane Veloso has since been transferred back to a prison in Yogyakarta, and her legal team plans to launch another appeal to prove she was a victim of human trafficking, according to Indonesian media.
Veloso's family and many in the Philippines continue to celebrate. Activists gathered outside the Indonesian embassy in Manila cheered early on Wednesday morning upon hearing the news, and the hashtag #MaryJaneLives quickly trended on Twitter.
Veloso's mother Celia told reporters: "A miracle has happened to my child."
But Indonesia's President Joko Widodo has insisted: "This is not a cancellation but a postponement."


A Dutch IVF treatment centre has said that 26 women may have been fertilised by sperm from the wrong man.

The Utrecht University Medical Centre said a "procedural error" between April 2015 and November 2016 was to blame.
Half of the couples who underwent treatment are pregnant or have already had children. They have been informed, the medical centre said.
"The UMC's board regrets that the couples involved had to receive this news," the centre said in a statement.
The statement said: "During fertilisation, sperm cells from one treatment couple may have ended up with the egg cells of 26 other couples.
"Therefore there's a chance that the egg cells have been fertilised by sperm other than that of the intended father."
Although the chance of that happening was small, the possibility "could not be excluded," the centre added.
The technique at the centre of the mistake involved a single sperm being injected directly into a woman's egg with a pipette. It is called Intra-cytoplasmic sperm injection (ICSI) and differs from in vitro fertilisation.
From April 2015 to November 2016, one of the lab technicians is believed to have used an inappropriate pipette to inject the sperm.
Although the pipette was changed each time, the technician used the same rubber top until he found traces of sperm in it and raised the alarm. The rubber top would normally have a filter, but in this case it did not, a hospital spokesman told the BBC.
Of the 26 couples involved, nine have had children and four women are pregnant. The other 13 embryos were all frozen.
All the couples are due to meet doctors from the centre in the coming days and will be offered the option of a DNA test.
The UMC carries out up to 700 ICSI procedures every year.
Dutch fertility support group Freya reacted with shock to the news. "Wanting a child is a very delicate thing, especially when it doesn't involve the normal bedroom way. So people need to have 100% confidence in the method they adopt," it said.
In 2012, a Singapore mother sued a clinic after it mixed up her husband's sperm with that of a stranger.
The woman, who was ethnically Chinese, suspected something was wrong when her baby had markedly different skin tone and hair colour from her Caucasian husband.


Crewe Alexandra have given manager Steve Davis full backing to carry on as manager next season in the wake of relegation from League One.

Speaking at a fans forum at Gresty Road, chairman John Bowler promised Davis a budget for next season on a par with the one he has had this season.
"We're not cutting back. We're putting in money that's sensible," said Bowler.
"We're finalising the budget but there is scope to bring in three quarters of the experienced players we need."
Bowler added: "In football, you have to realise that it's a results business and nobody is happy with this year. But we are setting ourselves out to be successful in League Two.
"We know what we've got to deliver and Steve has to lead that from the front. He says he's prepared to take on that challenge.
"I'm assuming that, if Steve's not happy with the support the board is giving him, then he'd look for another job."
Crewe, who have only won six league games this season, go into the final two games of the season eight points adrift at the foot of the table.
In his backing for Davis, English football's sixth longest-serving manager, Crewe chairman Bowler did issue a couple of cautionary directives.
Bowler made it clear at the fans' forum that Davis's position will be reviewed if the season does not start well.
He has also suggested that this summer's new arrivals, which may include popular former Alex striker Ryan Lowe, if he turns down the offer of a new deal at Bury, must prove more effective than last summer's.
In pointing out that recruitment "hasn't been as good as it needs to be", Bowler will back Davis, while "at the same not jeopardising the stability of the club".
"Signings haven't had the impact we thought they would," Davis told BBC Radio Stoke. "I'd hold my hands up to that. But the squad is now the youngest we've ever had. We have players with potential. I have to get that out of them.
"I know I've got the full confidence of the board and I'm grateful for the opportunity to restore a bit of lost confidence among the fans.
"When I was brought in we were 18th in League Two. I am still the right person. I know the circumstances if we don't start well but, if we can build some momentum early on, we can have a good season."


A British-born police officer working for the Edmonton Police force in Canada has been shot and killed.

Constable Daniel Woodall, 35, and another officer were shot while serving an arrest warrant at a home in west Edmonton on Monday night.
Woodall, an eight-year veteran of the police force who had been recruited from the Greater Manchester Police, died at the scene.
Police said on Twitter that they are "no longer looking for a suspect".
Woodall worked for the Edmonton Police force's hate crimes unit, and the arrest warrant he was serving was for criminal harassment.
Another officer, Sgt Jason Harley, 38, was shot at the same time, but was protected by his bulletproof vest. He has since been released from hospital.
Shortly after the shooting, a fire erupted at the home where the officers were serving the warrant.
Prime Minister Stephen Harper said in a statement, "Constable Woodall's service to Edmonton and to Canada will be remembered and honoured.  We grieve his loss today with Alberta and the rest of the country."
The CBC reports that the last member of the Edmonton Police force to be killed while at work was in 1990.
Edmonton Police Chief Rod Knecht is expected to offer more details at a news conference on Tuesday.


President Donald Trump has set in motion his plan to build an "impenetrable, physical, tall, powerful, beautiful, southern border wall" between the US and Mexico.

The border is about 1,900 miles (3,100 km) long and traverses all sorts of terrain.
Mr Trump says his wall will cover 1,000 miles and natural obstacles will take care of the rest.
But how much will it cost and who is going to foot the bill?
"I would build a great wall, and nobody builds walls better than me, believe me, and I build them very inexpensively."
Mr Trump claims the total cost of the wall will be $10bn (Â£7.5bn) to $12bn. But estimates from fact checkers and engineers seem to be universally higher.
Senate Majority Leader Mitch McConnell estimated it will cost between $12-15bn, as he addressed reporters at a Republican conference in Philadelphia.
The 650 miles of fencing already put up has cost the government more than $7bn, and none of it could be described, even charitably, as impenetrable, physical, tall, powerful or beautiful.
There are other reasons the costs would be likely to escalate beyond Mr Trump's price tag - his plans require extending the wall into increasingly remote and mountainous regions, raising the building costs substantially.
Adding even more to the expense, the new 1,000 miles would crisscross private land, which would have to be purchased, perhaps by legal force, or financial settlements made with owners.
A study by the Washington Post estimated the cost of the president's wall would be closer to $25bn.
President Trump has always insisted Mexico will pay. Mexican President Enrique Pena Nieto has been equally insistent he will not.
Needing to fulfil his election pledge to start building on day one, Mr Trump has signed an executive order setting it in motion.
He has accepted that US taxpayers will have to cover the initial funding.
Congressional approval would be needed and Republicans have suggested a supplemental appropriations bill could be fleshed out over the next two months.
There are a number of options, but nothing has been officially decided.
1. Raising tariffs on imports. Mr Trump's spokesman, Sean Spicer, said on 26 January that the president wanted a 20% tax on Mexican imports to pay for the wall, although he later added that it was one of several options still being considered. "By doing it that way we can do $10bn (Â£8bn) a year and easily pay for the wall, just through that mechanism alone," he told journalists. Forbes has argued that existing duties on Mexican goods would have to be quadrupled to pay for the whole of the wall, even if its cost were spread over 10 years. US companies would also almost certainly source products from elsewhere, reducing the revenue. The Mexican government could respond by removing tax benefits for US foreign investment. The investment totalled $101bn in 2013.
2. Remittances. Two possibilities here. President Trump could try to use laws aimed at preventing money-laundering to halt Mexicans working in the US from wiring money to families back home. The sector is huge - about $25bn a year. The hope is that the threat would cow Mexico into coughing up for the wall. The second option is to tax the remittances. Either a flat tax on all, or a far more punitive tax on those who cannot prove legal residence. But Mexicans affected by remittances might simply avoid using the wire companies and find undocumented third parties to transfer the cash.
3. Levying a "border adjustment" tax. House Republicans propose lowering corporation tax from 35% to 20% but base it on the place of consumption, not production. Imports would be taxed but not exports. A 20% tax, given the $60bn trade deficit with Mexico, would raise $12bn a year. Mexico could do little, the Washington Post reports, because border adjustments would apply to all US trading partners and would not therefore be seen as a singling out Mexico.
4. Increasing travel visa and border crossing fees. Targeting countries that have a bad record on illegal immigration, including Mexico, for higher visa fees would be popular among many Republicans. Along with increasing the fees on cars and individual people crossing the border it would raise revenue, but would probably not be enough alone.
Asked whether any of his solutions were realistic, he told the Washington Post: "It's realistic if you know something about the art of negotiating. If you have a bunch of clowns negotiating, it's not realistic."
Throughout his presidential campaign, Mr Trump was adamant that he would fortify the southern border with a wall ("a wall is better than fencing and it's much more powerful").
Concrete is the obvious choice. Ali F Rhuzkan, a New York-based structural engineer, estimated in an article for National Memo that a 1,900-mile wall - seemingly Mr Trump's original plan - would require about 339 million cubic feet (12.5 million cubic yards) of concrete - three times more than the Hoover Dam.
Mr Rhuzkan's estimate was based on a wall that ran 5ft beneath the ground and 20ft above. Mr Trump's claims for the wall range between 30ft and, more recently, 55ft. Even at 1,000 miles - vast amounts of concrete would be required.
That concrete, Mr Rhuzkan wrote, would need to be manufactured in slabs nearby - likely in dedicated plants - and transported to building sites, with all the enormous production and staffing costs involved.
However, since assuming office, Mr Trump's secretary of Homeland Security has said that parts of the wall will be transparent.
"There will be the physical wall and then parts of the wall that you can actually see through because it will rely on sensors and other technology," Secretary John Kelly told Fox News.
Free movement between the US and Mexico is not just a human issue. What would the construction of a wall mean for animals that live near the border?
The US-Mexico border region is a delicate ecosystem with regular animal and bird migrations moving between the north and south of the American continent.
A number of species need to cross the border to mate with their genetically different cousins, including the endangered North American jaguar and black bears, which would be threatened without being able to mate with Mexican bears.
The wall would also have to take into account natural flooding zones as well as large areas of sand, where the ground effectively moves.
Then there is the detrimental impact to the landscape of a massive construction project - digging, road building, and the appearance of a concrete wall up to 50 feet high, notwithstanding Mr Trump's pledge that it will be "very beautiful".


Triple world champion Elise Christie says she wants to make amends at the 2018 Winter Olympics in Pyeongchang.

The short-track speed skater was disqualified from each of her three events at the Sochi 2014 Olympics.
And the Scot, 27, who in March became the first British woman to win a world speed skating title, is out to put that behind her in South Korea.
"Part of me does need it, with what happened in Sochi and to get redemption for the mistakes I made," she said.
"I definitely want it more than anything else.
"I still have a few things I need to work on to perfect things going into the Games, but it mainly is just about the Olympics.
"I don't want to give everything I've got at the qualifiers. I want to save something so they can't analyse my performance and they don't know exactly how strong I am right now.
"I want to get a really good ranking of course, but for me it's about a really good performance at the Games, and to give them something they've not seen before."
Christie became triple world champion at the World Short Track Speed Skating Championships in Rotterdam earlier this year.
But she revealed winning the overall European Championship short-track speed skating title in the same venue as her Sochi disappointment was the initial hurdle to get over.
"The first thing was being European Champion in Sochi [in January 2016], which tackled it head on," Christie added. "And to have that little bit of success at the new Olympic venue [at the ISU World Cup event at Gangneung, South Korea] was a total restart for me.
"I was against the favourite, Choi Min-jeong - the previous world champion - and I managed to beat her in her home ground.
"I've got the upper hand in a way, it felt really good. I'm just so excited to get back out there."


Italy's first female astronaut, Samantha Cristoforetti, is spending almost six months on the International Space Station.

The European Space Agency astronaut arrived at the orbiting space lab on Monday, along with two crewmates from Russia and America.
But what exactly will she be doing during her time in space?
The ISS gives the chance to do scientific experiments that cannot be done on Earth, as the station offers an environment of microgravity.
Here we run through a few examples of the experiments on Samantha's 'to do' list...
Samantha will operate a gadget called an electromagnetic levitator, which can heat metals to 2,000Â°C and then cool them very quickly.
This will be a chance to see what happens to different metals when they go from liquid to solid, without the effect of the Earth's gravity.
It's hoped the results will reveal more about the physics of the metals and how they work.
Samantha will be testing new machine technology and how well they work in space, such as this astronaut joystick.
Using a joystick in space may feel very different in space compared to on Earth.
So these experiments will see how being in space might affect how well an astronaut can control a space robot or space machinery.
Another thing is that equipment may need to be attached to the astronaut so it doesn't float away. The testing will also see what impact this has.
Samantha will be doing lots of experiments to see how being in space affects her body.
For example, she will experience 16 sunrises and sunsets every day on the International Space Station and be tested to see how this affects her body clock.
Another important subject is food and energy. Experiments to see how much food an astronaut would need for a long mission will be carried out. Samantha will record what she eats and her energy levels over a period of time.
Other things that will be looked at include how space affects skin and why many astronauts get headaches.


The number of times police have used Tasers in Devon and Cornwall has nearly doubled over a two-year period.

Figures obtained by the BBC through the Freedom of Information Act show the stun guns were used 34 times in 2010 and 65 times last year.
Human rights groups say they were being used too readily.
Devon and Cornwall police said the rise could be linked to the increased number of officers now trained to use Tasers.
Of the force's 3,200 officers, 480 are trained to use Tasers, up from 150 before 2009 and spending on the weapon rose from Â£33,470 in 2009 to Â£101,379 last year,
           according to an FoI request
.
Nineteen of the 34 people that were shot with a Taser in 2010 were charged with an offence, and 37 of the 65 shot in 2011 were charged.
Eulette Ewart, from the human rights group Amnesty International, said Tasers should only be used in "limited circumstances " where there was a "serious threat to life or serious injury".
She said: "Given the increase, one must question whether the incidents in 2011 merited the need for a Taser to be drawn as opposed to 2010 when it was only drawn 34 times.
"We are not against Tasers but they are very dangerous and so they need to be used in a very limited set of circumstances."
The force's criteria for using Tasers
 states that they can be used if officers get permission from a senior officer and "in the course of their duty, may have to protect the public, themselves and /or the subject(s) at incidents of violence or threats of violence of such severity that they will need to use force".
Nigel Rabbits, chairman of the Devon and Cornwall branch of the Police Federation, the officers' staff association, wants most frontline officers to have Tasers.
He said: "In Devon and Cornwall, it has been recognised that Tasers are a really useful safety measure for officers and the public.
"They are really safe. Most people recover really quickly from a Taser and walk away."


UK ministers should back Swansea Bay's proposed tidal lagoon as £1bn extra is going to Northern Ireland as part of a Tory-DUP deal, Plaid Cymru has said.

A key review backed the energy scheme, but ministers said they were taking the time needed to consider it properly.
Energy spokesman Simon Thomas said the project could "unleash a level of private capital investment rarely seen in Wales".
It is claimed the lagoon could generate power for 155,000 homes over 120 years.
The Conservative deal with the Democratic Unionist Party, announced on Monday, means the 10 DUP MPs will back Theresa May's minority administration in key Commons votes and Northern Ireland will receive an extra £1bn over two years.
On Tuesday, UK Energy Minister Richard Harrington said the Hendry review identified "significant questions as to whether tidal lagoons can be cost-effective, and very complex issues are involved".
But Plaid Cymru has written to Chief Secretary to the Treasury Liz Truss urging her to get behind the scheme.
"It will see new industrial facilities built and new life breathed into Welsh industry - large and small," Mr Thomas said.
"The Conservative government has decided to end austerity in Northern Ireland because of its deal with the DUP. It is only fair that Wales gets investment as well."
In March, more than two thirds of AMs signed a letter asking the prime minister to back the power scheme.
Mr Thomas said the lagoon would bring opportunities for new ventures in leisure, tourism and associated maritime activities by potentially attracting large numbers of visitors and "contribute hugely to the image of Wales as a place where exciting and transformational projects can be imagined and delivered".
The developer needs to agree with UK ministers how much subsidy it should receive for the energy generated and to obtain a marine licence.


Ten people have been told they will have to move out of their care homes as the council is closing them.

Merry Hill House and Nelson Mandela House are the last remaining homes run by Wolverhampton City Council.
The decision to close them as part of a plan to save Â£134 million over five years was made at Wednesday's cabinet meeting.
Jessie Bunce, 86, who lives at Merry Hill House is "absolutely devastated" said a family friend.
Paul Tunney said: "Her daughter [is devastated] as well - they are both supporting and consoling one another. As yet we don't know where she is going to go."
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The Woden Resource Centre, a day care facility in Wolverhampton will also be shut as part of the plan.
Council leader Roger Lawrence described the closures as "unpalatable" but "unavoidable" due to government cuts.
Councillor Elias Mattu, cabinet member for adults, said: "I do not want any specific timescale set until we have spoken with all of the residents and their relatives."


Seventy organisations, most of which will be involved in implementing the biggest overhaul of the benefits system since the creation of the welfare state, have told MPs of their concerns about the government's plans.

BBC Radio 4's The World This Weekend has been shown the written evidence submitted to the House of Commons Work and Pensions Committee, which is examining the progress being made towards the implementation of the Universal Credit in the autumn of 2013.
In over 500 pages of testimony, organisations representing councils, charities, trades unions, business groups, housing organisations and the government set out their outlook on the changes.
Universal Credit attempts to address what Work and Pensions Secretary Iain Duncan Smith sees as the two principal failings of the current benefits system: complexity and failing to make it worthwhile to take up paid work.
Many of those who have submitted evidence to the select committee of MPs regard themselves as key to making sure this huge change works.
Many too, in evidence amounting to more than 200,000 words, acknowledge the government's motivations for reform are sound.
But two key themes emerge which suggest deep seated and broad based worries about the practicalities of making the idea work.
Firstly, a wide range of potential implications are raised both for prospective recipients of Universal Credit and those responsible for delivering it.
Secondly, there are serious concerns about getting the system up and running successfully in a year from now, by October 2013.
So what impact could the change to Universal Credit have?
The evidence shows there is widespread concern about managing Universal Credit online, the implications of it being paid monthly and being paid to one member of a household, and the gap when the current system is phased out and the new one starts.
Ministers are very keen to ensure that the new system should be "digital by default" - in other words, managed and run online.
"The new universal credit system risks causing difficulties to the 8.5 million people who have never used the internet and a further 14.5 million who have virtually no ICT skills," says Citizens Advice.
The public sector workers union Unison makes a similar point, as does the National Housing Federation, the umbrella group for homeless organisations, Homeless Link and Community Links, a charity based in east London, amongst others.
Concerns are raised too about paying Universal Credit monthly.
The Women's Budget Group, which describes itself as an "independent organisation bringing together individuals from academia, non-governmental organisations and trades unions to promote gender equality," also makes some observations.
It tells the MPs: "The government says monthly payment of Universal Credit mimics life in work.
"But many on low incomes in work have wages and/or benefits and tax credits paid more frequently, which matches common budgeting patterns for those on low incomes.
"Only one in ten of claimants think it would make their lives easier. Women are likely to be hit harder, as in low income families they tend to make more frequent purchases that will be squeezed as money is stretched."
There are concerns too that the payment of Universal Credit to one person in a household could, in some instances, upset the family dynamic: potentially putting that individual in a position of considerable power and influence.
Many of those who have submitted evidence are worried about how some people will cope when the changeover from the current benefits system to the Universal Credit takes place.
"What consideration has been given to providing grants to cover a shortfall when transitioning from fortnightly to monthly payments, rather than claimants having to rely on budgeting advances or 'pay-day loans' which need to be re-paid?" asks Gingerbread, the charity for single parents.
Manchester City Council raise a broader concern: the effects not just on people, but communities.
"We have concerns about the impacts on people but also on 'place' - either from large scale churn de-stabilising people and communities or reductions in income within areas with high concentrations of people currently on benefit."
Let's now turn to look at some of practical problems around making this change happen on time.
A wide range of organisations involved in meeting the government's deadline are clearly very worried about achieving it.
At the heart of the Universal Credit is what is known as the Real Time Information system. The aim is it will be much more responsive to people's changing circumstances.
It will require employers to report their employees' pay each time they are paid. In addition the self-employed will have to report their income every month instead of every year.
This will be a "significant and difficult burden, reliant on information from others", the Chartered Institute of Taxation tells the MPs.
The success of the Universal Credit depends on the new computer system being completed "under extremely tight timelines," the employers' organisation, the CBI says.
"The new system's tight delivery timetable, coupled with low awareness among companies, is a risk to business and to the implementation of the Universal Credit."
"There is a real risk that the central government Universal Credit IT systems will not be ready on time," adds the Local Government Association, which represents councils.
So how does the government respond? Radio 4's The World This Weekend invited a minister to appear on the programme, but the invitation was declined.
In its evidence to the committee of MPs, the Department for Work and Pensions claims that "digital skills are a factor in around 72% of jobs", and so encouraging people to manage their Universal Credit online is sensible. It also saves a significant amount of money.
Advice will also be available, the department says, for those recipients who need help with managing their family budget.
"Rigorous, integrated IT testing has also commenced," it adds, pointing out it has "some of the best contingency arrangements in place across government" if things go wrong.


Ghana international goalkeeper Adam Larsen Kwarasey has joined Danish side Brondby from Norway's Rosenborg.

The 29-year-old, who withdrew from Ghana's 2017 Africa Cup of Nations squad with a back injury, has signed a four-year deal until December 2020.
"We have signed a very experienced player who is keen to win," Brondby sports director Troels Bech told the club's website.
Kwarasey has won league titles with his last three clubs.
He enjoyed success with Strømsgodset (Norway), MLS side Portland Timbers of Major League Soccer and Rosenborg BK.
Meanwhile, another Ghanaian on the move is Liberty Professionals midfielder Latif Blessing.
He has sealed a three-year deal with Major League Soccer side Sporting Kansas City.
Blessing, 20, was voted the 2016 Ghanaian Premier league's Most Valuable Player and was the top scorer with 17 goals for Liberty.
His scoring form in the domestic league prompted Ghana coach Avram Grant to include him in his provisional squad for Gabon.
Sporting KC Manager Peter Vermes believes signing Blessing, who has an option of additional year, will give the player a platform "to reach his potential".
"We have scouted Latif and been very impressed with what we've seen from him," Vermes said.
"The great thing we love about him is that he is young, but with a lot of potential as evidenced by his goal scoring record with his previous club.
"With every player you acquire, you always feel they have potential, but we also think he has a great attitude, and we think he has the ability to reach his potential with our club."


Leading Sri Lankan opposition figure Sarath Fonseka has held his first big political gathering since serving two years in jail after losing a presidential election.

The former general called for major political reforms.
But the BBC's Charles Haviland in Colombo says that disunity among the opposition meant the turnout was low.
Mr Fonseka unsuccessfully stood against President Mahinda Rajapaksa in a presidential election two years ago.
But he lost after a vitriolic campaign and was imprisoned shortly afterwards.
Mr Fonseka's lawyer said in May that the terms of his release prevented him from running for office for seven years.
But that has not stopped the former general - credited with playing a leading role in defeating Tamil Tiger rebels in the country's civil war that ended in 2009 - from re-entering politics.
He and his supporters have pledged to fight constitutional changes which have made President Rajapaksa one of the world's most powerful presidents.
They also strongly criticised what they said was the breakdown of the rule of law and the undermining of democracy in Sri Lanka.
Our correspondent says that although nearly 1,000 people including many Buddhist monks attended the rally and stayed despite a heavy downpour, the turnout was much lower than Mr Fonseka would have wished.
The former general is at loggerheads with Ranil Wickremesinghe, the leader of the main opposition party, who ordered his colleagues not to attend the rally.
Many of those who did go to it were strongly critical of Mr Wickremasinghe's move, accusing him of creating divisions and sectarianism within the opposition.
But it appears that the president has shrewdly succeeded in using the release of his great rival to fragment the opposition, our correspondent says, and the president - still popular with the Sinhalese majority - seems more powerful than ever.


World number one Andy Murray progressed to the third round of the Madrid Open with a straight-set victory over Romanian Marius Copil.

The 29-year-old Briton, who had a first-round bye, won 6-4 6-3.
Murray was not at his best early on but broke world number 104 Copil at 5-4 to take the first set and pounced again at 3-2 in the second.
He will face Croat Borna Coric or Frenchman Pierre-Hugues Herbert in the last 16.
Following his victory, Murray told BBC Sport: "The last few weeks my serve hasn't gone particularly well.
"Obviously when I was coming back from my elbow injury that was the one thing that I wasn't able to practise in my time off and that showed a bit in my matches.
"I was broken six times in one match, seven in another. I wanted to come here, serve a little bit better and I did that today.
"Today was the start and I have to get better, but at least I gave myself the chance to play another match in a couple of days. It is a very, very important period of the year."
It was a solid display from Murray against a potentially dangerous opponent as he prepares for the French Open, which starts on 28 May.
Copil will move into the world's top 100 next week, and the 6ft 4in Romanian was the more aggressive player in the first set.
It took Murray until the 10th game to break his serve, and he finally prevailed through attacking Copil's shaky backhand.
The Briton looked far more focused in the second set as he wrapped up victory in one hour and 23 minutes - with just nine unforced errors and without facing a break point.
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Murray reached the final in Madrid last year, losing to Novak Djokovic, and took the title in 2015, but has so far had a mixed clay-court season.
After taking a month out due to the elbow injury and withdrawing from Britain's Davis Cup quarter-final defeat by France, he lost in the Monte Carlo Masters last 16 on his return.
The Scot was beaten by Austrian Dominic Thiem in the semi-finals of the Barcelona Open last month.


A car owner whose vehicle was written off after a bin lorry knocked down the car port outside his house, has told of the "shock and upset" of the incident.

Mario Kyriacou was working at home when his Audi convertible was destroyed in Ranger Walk, Colchester.
He said he heard a noise "like thunder", initially mistaking it for a car crash until he was alerted by neighbours to the damage outside.
The council has apologised, saying the matter is with their insurers.
Mr Kyriacou, who works in advertising and marketing, heard refuse collectors arrive to empty bins near his home, he told the Evening Gazette.
He said: "I heard a massive crash, it was like thunder and at first I thought it could be a car crash, but I didn't really think twice about it as they're a noisy lot."
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It was only a few hours later when his neighbour came in to ask him if he had "seen the car port below" that he looked out.
"I obviously swore a lot. I can't express how shocked I was, and upset. And then it was explained to me that the bin lorry had backed in and knocked down the car port," he said.
Mr Kyriacou said it was only chance that his Audi, which he bought for Â£12,000 five years ago, was parked there, as usually another neighbour used the space in the car port.
A Colchester Borough Council spokesman said it regretted the incident and apologised for the "understandable upset and distress" it caused.
He said: "We are moving as fast and as far as we can to ensure that reparations for the damage are made as soon as possible."
A motorbike, owned by Paul Church, was also damaged in the incident.


It was the Washington Post that first coined the term in 1986.

"The fast-food factories: McJobs are bad for kids" a headline announced over a report about thousands of teenagers employed in McDonald's US kitchens.
The term took hold, to such an extent the Oxford English Dictionary still defines McJobs - 30 years later - as a catch-all for "unstimulating, low-paid jobs with few prospects, especially ones created by the expansion of the service sector".
Job insecurity is a common feature.
Fretting about "McJobs" has returned as the world of work changes rapidly.
And whoever wins the next general election will need to deal with this most fundamental of changes, away from the world of the nine-to-five, permanent job with a single employer, and towards a world of flexibility where people and technology become more entwined.
The very wealth of our economy depends on riding this wave - a global trend - successfully.
One of the first challenges the new prime minister will face is how to react to the most significant inquiry into the new world of work at present being finalised by Matthew Taylor, the head of the Royal Society of Arts.
He was commissioned to undertake the review by Theresa May last autumn, and has said he will deliver the report to Number 10 shortly after 8 June.
Much of this new world of work is said to be negative.
The number of zero-hours contracts - which offer no guaranteed work - has grown from 143,000 in 2008 to over 900,000 now.
Alongside that development comes the expansion of "self-employment" which has accounted for 45% of all employment growth over the same period (although it is worth remembering that more than 80% of working adults are still in more traditional, permanent employment).
Are zero hours contracts simply the return of "casualisation", where employees are at the beck and call of profit-hungry and often unscrupulous employers?
Or a nod to new, modern needs for flexibility, so that work can be balanced with the rest of life?
Is hiring from the new army of the "self-employed" simply a way of businesses avoiding tax and pension responsibilities and bypassing the rights - such as holiday and maternity leave - guaranteed to full time workers?
Or a nod to individual autonomy, where people work to their own rhythm and receive just reward for their entrepreneurial flair?
Of course, it depends which businesses you speak to.
Especially if it's the business that was the original butt of the McJobs attack - McDonald's.
"We have restaurant managers that look after 100 people, they are running businesses over Â£2m [in revenues] and they are responsible at a young age for their fortunes and their future," Paul Pomroy, the chief executive of McDonald's UK, told me.
Many of those managers started in the kitchens - not actually flipping burgers, it turns out, as machines fry the beef patties on both sides and there is no need to turn them over.
Indeed, when I put it to one manager, Liz Stephenson, that working in McDonald's is not all "flipping burgers", she replies archly: "I've never flipped a burger."
Snobbery is one word that comes to the mind of people like Liz when they consider how some view a career like hers, which started behind the counter on casual hours when she was at school and now involves being the company point person for restaurant managers who are running businesses with revenues counted in the tens of millions of pounds a year.
We have long had a rather romanticised vision of manufacturing jobs - even low-skilled ones - and have yet to fall in love with the service economy - such as retail - despite the fact it makes up the vast proportion of our economy.
"McDonald's offer training and a real career," Ms Stephenson (who is off to Chicago to receive a global company award for her achievements) tells me. "I've heard all the jokes."
Whatever the protestations of businesses which say they have worked hard improving their employment practices (McDonald's offers zero-hours workers rights to sick and holiday pay and has never demanded employees abide by "exclusivity clauses"), chief executives know controversies over companies such as Sports Direct and Uber can muddy all their reputations.
"Businesses take decisions that do damage," Mr Pomroy said, making clear he is not referring to any specific examples.
"Businesses in the modern world need to open up more, be transparent and be honest about how they treat their people and how they treat their customers.
"The internet has such a vast array of information, you can't sit back and hide anymore and not be front foot."
He added: "People up and down our workforce want to be treated with respect, they want a fair chance, they want progression, they want to have fun when they are working, they want to feel part of a team.
"I want to be able to walk into our staff rooms and look people in the eye and know we are treating them fairly - whether it is the 16-year-old school leaver or the 35-year-old mum who is using our flexible contacts to interweave with childcare."
Mr Pomroy dismisses claims that zero-hours contracts, for example, are simply a method for firms to keep people in insecure, low-paid work.
As I wrote last month, when offered the chance to move on to fixed-hours contracts, 80% of McDonald's staff affected said they preferred zero-hours.
The other big, robotic, beast in the room when it comes to the new world of work is technology.
The fear is that while we worry about zero-hours and self-employment, artificial intelligence and computers that can crunch "big data" in the blink of an eye are going to replace millions of us in the workplace.
For services industries like his, Mr Pomroy is not so sure.
"Since we have introduced technology - you can place your order on giant screens - it hasn't actually saved us labour in terms of reducing the number of people we need," he said.
"We've actually used that as a springboard to put more people out in the dining area, so giving hospitality.
"We've introduced table service. Using technology to enhance the customer experience is what is critical - not cutting the number of jobs we offer.
"So since we have been introducing technology, we've recruited a further 5,000 people - taking our total workforce to 115,000."
That jobs growth will continue, he insists, revealing plans to recruit 2,000 to 3,000 jobs a year.
"We have over half our restaurants open 24 hours a day, five days a week, and there is still opportunity to extend the number of restaurants that operate 24 hours a day, seven days a week.
"We are also a growing business. We have had 11 years of consecutive sales growth. I've got no plans to slow that down."
In 2007 McDonald's launched a campaign to have "McJobs" removed from the dictionary.
They are still trying.
"I would love it to go," Mr Pomroy said.
"Not for me, I'm the CEO. It's more for the 115,000 people that work in our restaurants; they would love it to be removed."
McDonald's spawned the "McJobs" tag in the 1980s and insists it has moved on.
Mr Pomroy's problem is that other businesses could now be taking on the mantle as the new world of work throws up a very 21st century challenge.


Footage showing German soldiers in Guernsey during World War Two has been uncovered.

The images, recently restored in Jersey by Kevin Lewis, are understood to have been filmed by troops chronicling their occupation of the island.
It was owned by John Davies who moved to Jersey from Wales in 1929 and had business interests in Guernsey.
Mr Lewis said the footage was probably last watched shortly after the war in the late 1940s.
The video is about seven minutes long, which Mr Lewis said could make up a significant part of all available footage of the occupation due to restrictions on filming put in place by the German authorities.
The 16mm films were discovered in Jersey amongst Mr Davies personal effects after his death. It is believed the footage was "liberated" from German soldiers in Guernsey.
It depicts aspects of ordinary life and training for the German soldiers, including firing anti-aircraft guns and driving tanks.
Kevin Lewis, who restores old films as a hobby, said projects like this have challenges of their own.
"The film was very, very concave. It was very old. The only way I can show it is to put it in the projector backwards and project it through a mirror.
"Sadly, if a great uncle passes away all of these films go into the skip. I can often be seen climbing into skips saying 'this is our heritage, when it is gone it is gone and we need to preserve it'," he said.
The film is being offered to the Imperial War Museum to be re-printed and fully restored before being put into the Jersey Archive.
Channel Islands occupation


A camera focused on a bus lane has generated nearly £1m in fines in six months.

Sandwell Council introduced the camera on New Street, West Bromwich in December. Since that time it has issued 48,755 penalty charges to drivers.
Motoring organisation the RAC said the volume of fines was a "significant worry" and added the camera was already among England's most lucrative.
The council said the money was being reinvested in safety schemes.
"When they started to enforce it [the lane] with a camera, it caught many motorists unaware," RAC spokesperson Pete Williams said.
"I think alarm bells have to ring when you start getting such a high volume of fines.
"Most motorists do not set out to break the law."
He said the camera, which has so far raised £944,832 - amounting to 270 penalties a day, or one every six minutes - was already one of the most lucrative bus lane cameras in England, coming "a close second" to John Dobson Street, in Newcastle.
However, Sandwell's cabinet member for highways and environment, David Hosell, said: "Any money that is made from the camera is put into highways projects and safety schemes.
He added that while £1m "might sound like a great deal of money", the scheme had also cost a lot to set up.