A "sugar tax" should be introduced by the UK government to help curb obesity in childhood, a campaign group says.

Action on Sugar has produced a seven-point plan to discourage children from consuming foods and soft drinks with high levels of added sugar.
The group wants measures brought in to cut added sugar in food by 40% by 2020, to cut fat in foods and to ban sports sponsorship by "junk food" companies.
The Department of Health has said it will consider the recommendations.
Action on Sugar is a group of specialists concerned with sugar and its effects on health. It says one in five 10 to 11-year-olds in the UK are now obese, while one in three are overweight.
The group has produced an action plan for the government following a request for its views from Health Secretary Jeremy Hunt.
The seven proposed measures are:
The group's chairman, Prof Graham MacGregor, said current policies were not working and that obesity could be prevented if "the food environment is changed".
"The UK requires the implementation of this coherent strategy, starting by setting incremental sugar reduction targets for soft drinks this summer. No delays, no excuses," Prof MacGregor said.
Dr Aseem Malhotra, cardiologist and science director of Action on Sugar, said it was "really quite shameful that the food industry continues to spend billions in junk food advertising targeting children".
"It's time to bust the myth of physical activity and obesity and dissociate junk food and sport," he added.
A Department of Health spokesman said: "We know some people eat too many calories including sugar. Childhood obesity is at its lowest since 1998 but more should be done.
"Next week we will get expert scientific advice on sugar which will help shape future thinking. We will consider these recommendations as part of this."
Earlier this year Dame Sally Davies, the chief medical officer for England, said a sugar tax may have to be introduced to curb obesity rates.
She told a committee of MPs that she believed "research will find sugar is addictive", and that "we may need to introduce a sugar tax".


Iraqi PM Haider al-Abadi has visited Mosul to congratulate Iraqi forces for their "victory" over Islamic State militants in the city.

The city was "liberated", with "just one or two pockets" still controlled by IS, his office said in a statement.
Iraqi forces, backed by US-led air strikes, have been battling to retake Mosul since 17 October last year.
Islamic State militants seized it in June 2014 before proclaiming a "caliphate" straddling Iraq and Syria.
Kurdish Peshmerga fighters, Sunni Arab tribesmen and Shia militiamen have also been involved in the gruelling battle.
The Iraqi prime minister arrived to "congratulate the armed forces and the Iraqi people" on the final defeat of IS in Mosul on Sunday, the statement said.
"Victory is certain, and what remains of [IS] is surrounded, and it is just a matter of time for us to announce the great victory to our people," Mr Abadi said.
There were celebrations in the streets during Mr Abadi's visit but he has not yet given a speech formally declaring triumph.
His office says victory will be formally declared after Iraqi forces clear out the remaining pockets of jihadists desperately holding out in a tiny area near the Old City.
Airstrikes and exchanges of gunfire could still be heard on Sunday, and plumes of smoke seen rising into the sky.
The fall of Mosul does not mean the end of IS in the country. It still has territory elsewhere - such as Tal Afar and three towns in the western province of Anbar - and is able to carry out bombings in government-held areas.
Jonathan Beale, BBC defence correspondent
Troops helped a steady stream of fleeing civilians - mostly women and children - to safety. Their faces were haunted and some had to be helped.
The children didn't even flinch when there was more sound of gunfire. An older woman was so weak she could barely walk. A few babies being carried looked almost lifeless.
If this is victory it's come at a huge cost. Not just in human life. Nearly everyone rescued had had to leave dead relatives behind.
Almost every building in the old city has been scarred or completely destroyed.
Search and rescue teams are still pulling bodies from the rubble. The heat has contributed to the stench of decaying corpses.
Read more
The government announced the "liberation" of eastern Mosul in January, but the west of the city, with its narrow, winding streets, has presented a more difficult challenge.
Some 900,000 people have been displaced from the city since 2014 - about half the pre-war population - aid organisations say.
Sally Becker, an aid worker with Road to Peace, an NGO helping children get access to medical treatment in war zones, said it was the "worst devastation that I've ever seen".
"I've been working in conflict areas now for 25 years, so I've seen most of them: Bosnia, Kosovo, Chechnya, and I have never seen anything as bad as this," she said.
Save the Children warned of the psychological impact on the children "haunted by memories of extreme violence, or of loved ones killed in front of them".
"For children and their families to process these horrors and rebuild their lives, psychological support will be absolutely crucial", said Ana Locsin, Save the Children's Iraq country director.
"But right now the world is providing next to no funding for mental health."
French President Emmanuel Macron and British Defence Secretary Michael Fallon are among those to congratulate Mr Abadi, and thank soldiers - including French and British troops - for liberating the city.
In a joint statement, EU foreign affairs chief Federica Mogherini and its aid commissioner Christos Stylianides said: "The recovery of Mosul from the hands of (IS) marks a decisive step in the campaign to eliminate terrorist control in parts of Iraq and to free its people."
They urged called for a "process of return and the re-establishment of trust between communities".


League One promotion rivals Bradford and Sheffield United had to settle for a point each after serving up a six-goal thriller at Valley Parade.

The visitors went in front in the 18th minute when Mark Duffy delivered a cross from the left, with leading marksman and skipper Billy Sharp scoring with a close-range header off the underside of the crossbar.
However, Bradford hit back to equalise in the 35th minute when the visitors' defence failed to cut out Matt Kilgallon's low cross from the left and Billy Clarke scored with a shot just beyond the far post.
United regained the lead after 51 minutes with another Duffy-Sharp combination. Duffy played a free-kick from the left deep into the Bradford goalmouth for the on-rushing Sharp to score from close range.
Bradford equalised for a second time 10 minutes later through Jordy Hiwula. United failed to clear a corner and, when Josh Cullen lobbed the ball back into the goalmouth, James Hanson played the ball across the face of goal for Hiwula to score at the far post.
The home side took the lead for the first time in the 68th minute when Kilgallon's left-wing cross was turned into the far corner of the net by Timothee Dieng.
The lead lasted a mere four minutes as, when the Bradford defence failed to clear John Fleck's corner, Chris Basham scored an equaliser with a shot at the far post to extend the Blades' 10-match unbeaten run.
Both sides tried to force a winner, with Bradford going closest five minutes from the end when Hiwula saw his shot rebound off the crossbar.
Report supplied by the Press Association


Google's YouTube is starting a subscription service that allows users to stream ad-free music videos and to download them for offline use.

The Â£9.99 monthly fee for Music Key also provides membership to Google Play All Access, its existing "all-you-can-eat" song stream and download facility.
It is set to pose a challenge to Spotify, Rdio, Beats Music and other audio-only "unlimited" music services.
The launch had been delayed by a dispute with independent labels.
However, Google said it had now signed deals with hundreds of indies worldwide.
That has enabled it to include tracks from artists including Billy Bragg, who had previously said YouTube was trying to "strongarm" labels into agreeing to "low rates" by threatening to block their material altogether if they did not take part.
He told the BBC his music had been included as part of an agreement signed by Merlin - which represents indie labels - but that he had not been informed about the details.
The BBC understands that the terms of the deal state that the more plays a video has, the bigger the share of the subscription pool its publisher receives.
Brad Nevin, chief executive of The Orchard group of indie labels, said he thought the deal struck was both fair and "a phenomenal opportunity".
Android devices will be first to be able to save clips, followed by Apple's phones and tablets, but the facility will not extend to PCs yet.
The mobile devices will also be able to continue playing music in the background when they switch to other programs.
In addition to album tracks, Music Key offers downloads of concert recordings, remixes, "unreleased" rarities and cover versions recorded by others.
YouTube describes itself as "the biggest music service on the planet", but Google Play is thought to lag far behind Spotify's 12.5 million paying subscribers.
One expert said the new offer might tempt a number to jump ship.
"If you are someone who only listens to Spotify and doesn't listen to YouTube, this won't be a good enough reason to switch," said James McQuivey, principal analyst at the Forrester Research consultancy.
"There is a certain comfort in the well-established digital habits that people already have.
"But if you - as many people do - listen to both Spotify and use YouTube for music, then this is genuinely a reason to switch, because you not only have all the unlimited music but also the ability to move from audio to video, which is a very compelling experience."
Those unwilling to pay can still access a new Music home page on YouTube's apps and web service, which:
Should Spotify, the market leader in music streaming, feel able to relax?
Maybe not - there is now a new revenue stream available to artists, many of whom are disgruntled with what Spotify is paying them.
It's not clear that YouTube Music Key will pay more - but if others follow Taylor Swift's lead and desert Spotify, that could signal a shift in the balance of power in digital music.
Read Rory's blog in full
Although Google says the new services will launch over the coming days, subscriptions will be available only to selected "beta" testers for the first six months.
Anyone can apply to join, but they need to be based in the US, UK, Spain, Portugal, Italy, Ireland or Finland.
Following the test, the general public will be invited to pay the $9.99/Â£9.99/9.99 euro monthly fee - the same price currently charged for Google Play All Access on its own. The beta testers will get a discounted rate.
Video downloads are offered in 320p standard definition and 720p high definition formats, and must be stored on a mobile device's built-in memory. Qualifying clips are flagged by a blue label.
Third-party tools have long given people a way to copy videos from YouTube to PCs, in breach of the site's terms and conditions.
However, until now this has not been possible via apps distributed on Google's Play marketplace and Apple's App Store.
Mr McQuivey said that YouTube's challenge was to convince its youthful audience that the convenience of downloading videos directly to a smartphone or tablet was worth the requested fee.
"YouTube is a form of cheating the music system, and has been for a long time, because people have been putting music up there without authorising it from the labels," he said.
"YouTube goes through an elaborate process to identify it and put ads around it. But it's not too far, in the user's experience, from piracy.
"When Napster went legit, it thought it could take its brand equity among a young audience and transfer it into a subscription service, and that didn't work out quite so well.
"The onus on YouTube is to make this the simplest transition that twenty-somethings can make."


In April 2014 the cybersecurity world was rocked by the discovery of Heartbleed, the name given to a vulnerability found in one of the systems we use to securely communicate over the internet.

At the time, as is often the case with new vulnerabilities, we had no handle on how widely it had been exploited - if at all.
In this hack - which investigators are calling the largest theft of consumer data from financial institutions ever - the Heartbleed bug was exploited to gain access to "Victim 2", an as-yet unnamed financial firm headquartered in Boston.
But it's just one angle to this enormous attack.
The real damage appears to have been done with some social engineering, executed in a way that shows just how difficult it is to defend against determined cybercriminals.
According to investigators, hackers gained access to various networks belonging to JP Morgan and six other financial institutions, scraping personal data they would then use to manipulate stock prices.
Other hacks targeted financial news organisations.
The three indicted men - Israelis Gery Shalon and  Ziv Orenstein and American Joshua Samuel Aaron - were conducting "security fraud on steroids", prosecutors say.
Another man, Anthony Murgio, was charged over running an illicit operation trading virtual currency Bitcoin.
This is how prosecutors say they did it.
The hacking technique often involved using legitimate accounts belonging to Joshua Aaron.
Using this legitimate access, as if Mr Aaron was a normal customer, paved the way for the hackers to gain access to networks and systems containing reams of data about other customers - people who were investing in stocks.
Over the course of several years, they stole personal data on more than 100m people.
The hackers didn't access bank details. They didn't need nor want them.
Investigators said the hackers used the personal details to send out information to bosses' email addresses, promoting certain stocks that hackers had bought cheaply. The price would rise, and the hackers would then sell off their now very valuable shares.
It's a technique known as "pump and dump".
Could the banks have done more? It's hard to say.
There was at least one instance when one firm noticed something was a bit amiss - but wasn't able to stop it.
The hackers were said to be using a remote server in Egypt to access the network of "Victim 3" - a financial services firm based in Omaha, Nebraska.
The remote server, which covered the accused's real location, was used to log in to Mr Aaron's account with Victim 3.
When info-security staff at the firm noticed the odd sign-in location, it locked Mr Aaron's account. Good security practice.
But, according to the court papers: "Aaron called Victim 3 and, upon being notified that his account had been locked and asked by a customer service representative whether Aaron had been traveling in Egypt in March 2014, Aaron lied to the representative, and claimed that he had been in Egypt.
"In truth and in fact, and as Aaron well knew, Aaron had not been in Egypt and was merely attempting to convince Victim 3 to allow Aaron and his co-conspirators to access Aaron's account online in furtherance of their efforts to hack into Victim 3."
For banks - indeed any big company online - there's a constant balance between making a system as secure as possible, but not locking it down so much that its frustrating for normal customers to use.
Investigators have called it the largest theft of consumer data from financial institutions ever.
But that's not all these men are accused of doing.
According to the court papers, the men were involved in a bingo card's-worth of online crime.
As well as the stock manipulation, and running a Bitcoin trading platform to help launder the cash, the men were said to be running illegal online casinos, selling fake antivirus software and - that age old internet scam - offering the purchase of pharmaceuticals.
All of this added up to an alleged haul of $100m, kept in bank accounts in Switzerland.
Follow Dave Lee on Twitter @DaveLeeBBC


Somerset and England wicketkeeper-batsman Craig Kieswetter has announced his immediate retirement from cricket because of an eye injury.

Kieswetter broke his nose and damaged his eye socket and cheekbone while batting against Northants last July.
The 27-year-old played 46 one-day internationals and 25 Twenty20 matches for England, but has not featured for his country since January 2013.
"I feel mentally I will never again be the player that I was," he said.
"I have had a terrific career, with plenty of ups and occasional downs, and I am calling time on my career and walking away with no regrets."
Kieswetter, who sustained his injuries when a delivery from Northants' David Willey went through his helmet grille, has struggled to regain perfect vision.
Having undergone surgery, he did briefly return to action for Somerset in September, before heading out to South Africa to play for Warriors in their domestic T20 competition, scoring 199 runs in 10 outings.
But during that period he realised his vision was still impaired and, after confirming in January that he would miss the 2015 season, he has now opted to retire from the sport.
He made his England ODI debut against Bangladesh in 2010, and opened the batting as they won the World Twenty20 later that year - the first time England had won a World Cup in any form of cricket.
Media playback is not supported on this device
Kieswetter was man of the match as England thrashed Australia in the final.
"This is sad news for all concerned," said Somerset director of cricket Matt Maynard.
"Craig is a very popular member of the squad and has made a real impression on the club during his years here. He has been a major influence both on and off the field and will be missed by players, coaches, staff and fans alike.
"At his best Craig was one of, if not the most, explosive keeper-batsmen in the game. He is an extremely gifted cricketer who could win a game on his own.
"His record speaks for itself and the game will miss him.  I would have loved to have worked with him this year but it just wasn't to be."
In both first-class and one-day cricket Kieswetter averages just under 40, while in T20s his average stands at 31.76. Domestically, he took over 500 catches throughout his career.
The wicketkeeper-batsman, who will lead the Somerset team out against Taunton in the T20 Blast on Friday, first came to prominence with the county when he took over the gloves during the course of a Second XI Championship match against Glamorgan in May 2006.
"I'll have so many memories of a career that spanned nine years of my life during which I have made so many friends. See you all on the sidelines," he added.


Archaeologists in Egypt have unearthed what they describe as a city that dates back more than 5,000 years, containing houses, tools, pottery and huge graves.

It lies by the River Nile, close to the Temple of Seti the First in Abydos.
Experts say the size of the 15 newly discovered graves indicates the high social standing of those buried.
It is believed the city was home to important officials and tomb builders and would have flourished during early-era ancient Egyptian times.
The discovery comes at a time when the country is trying re-energise its tourism industry, which has suffered amid militant violence since President Hosni Mubarak was overthrown in 2011.
Archaeologists have made a range of finds in the newly-discovered city including buildings, shards of pottery and tools.
It is believed that this location was home to important officials and tomb builders who may have been engaged in the construction of royal graves in the nearby sacred city of Abydos - a place of many temples, and a capital in an early period of ancient Egyptian history.
The area is in the southern province of Sohag, in Upper Egypt, home also to the city of Luxor, one of the country's most popular tourist sites.
"About a mile behind where this material is said to be we have the necropolis with royal tombs going from before history to the period where we start getting royal names, we start getting identifiable kings," Prof Chris Eyre, an Egyptologist based at the University of Liverpool, told the BBC.
"So, this appears to be the town, the capital at the very beginning of Egyptian history."
The discovery was made by an archaeological mission that belongs to the country's Antiquities Ministry, and not a foreign group, officials quoted in Egypt Independent website said.


A water sports centre has pleaded guilty to corporate manslaughter after a girl was killed in a fall from an inflatable banana boat ride.

Mari-Simon Cronje, 11, was hit by the boat which had been towing the inflatable at the Prince's Sporting Club in Bedfont, west London, in 2010.
Her father Andre Cronje said the firm had "individually and collectively avoided taking responsibility".
The company was fined £135,000 after it accepted culpability for the death.
Frederick Glen Walker, a director at the firm, was cleared of any offences at Southwark Crown Court.
Mr Walker, from Cobham, Surrey had faced a charge under the Health and Safety at Work Act, but the Crown Prosecution Service dropped the charges against him.
The company is no longer in operation.
Following the hearing Mr Cronje said: "We are, and always will be, deeply disappointed by the conduct and behaviour of the boat driver, the management and the owner of PSC.
"There was no appreciation for the risk inherent from towing the children in the water. Emergency procedures were not in place. This directly contributed to Mari-Simon's death.
"They (PSC) have individually and collectively avoided taking responsibility for the substandard way this was carried out."
Judge Alistair McCreath said: "I propose to fine the company every penny that it has. I have no greater power to do anything other than impose a fine and I cannot impose a greater fine than all of its assets.
"The principal culpability was to promote this activity to take place in circumstances where there were no onlookers.
"It doesn't seem to me to be anything other than absolutely obvious that if a large group of children are towed behind a speedboat... there should be somebody on board to keep an eye on that [inflatable]."
Mari-Simon was attending a children's birthday party and was part of a group riding the inflatable on a lake at the site.
The court heard that there were several health and safety failings.
The driver, New Zealander Matthew Gibson, had no UK-recognised qualification despite having five years' experience as a ski-boat driver, and staff said there was a "lax" attitude to health and safety.


In an era of high-security air travel, many a passenger has fallen foul of the rules banning liquids on planes.

But now an Italian airport has decided to waive the 100ml maximum limit - as long as the liquid is pesto.
More than 500 jars have made it through since Genoa's Cristoforo Colombo airport launched the "Il pesto Ã¨ buono" (Pesto is good) scheme on 1 June.
The cost? A donation to Flying Angels, which flies sick children abroad for treatment.
Pesto - a popular pasta sauce made with basil, cheese, and pine nuts - is a local speciality in Genoa.
The airport said the brainwave arose after staff were faced with "hundreds of jars that were seized in airport security checks".
Tourists with pesto jars of up to 500g can ask for a special sticker in exchange for a â‚¬0.50 (Â£0.44; $0.55) charity donation - although the airport says many are donating more.
The pesto is then scanned in a special x-ray machine before proceeding onto the plane as hand luggage.
Foreigners are not the only ones grateful for the pesto-preserving initiative. According to the airport, Genoese travelling out of Italy are delighted to find they can take the much-loved foodstuff along.
There are some rules, however: Passengers can take either one 500g jar, or two jars up to 250g. They must be flying directly from Genoa.
And crucially, the pesto must be Genovese.


Scenes for new superhero movie, Avengers: Infinity War, are to be shot in Scotland, according to newspaper reports.

The Sunday Mail and Daily Record said locations in Edinburgh, Glasgow and the Highlands are to be used in filming due to start next month.
Infinity War is part of the Marvel "universe" of superhero stories.
Scenes for Marvel's 2011 movie, Captain America: The First Avenger, were shot in Culross in Fife.
Rival comic publisher and film-maker, DC Comics, has also used Scotland for one of its superhero movies.
Scenes for 2012's Batman film The Dark Knight Rises were shot over the Cairngorms.
The action involved a C130 transport plane that was based at Inverness Airport for several weeks.
Stuntmen and a film crew also made parachute jumps over Cairngorm Gliding Club's airstrip at Feshie Bridge for the scenes.
The fuselage of a Jetstream aircraft that had belonged to Inverness-based airline Highland Airways plane was used to portray the interior of the CIA aircraft in the movie.
Infinity War is expected to bring together a huge cast of Marvel heroes and villains, and the actors who play them.
Reportedly they include Brie Larson as Captain Marvel, Chris Evans' Captain America, Benedict Cumberbatch's Doctor Strange and Inverness-born Karen Gillan's Nebula, a character from Marvel's Guardians of the Galaxy comics and movies.
Disney has so far not commented on the reports Scottish locations are to be used for the film, which is to be released next year.
National arts development agency, Creative Scotland, said it could not give a comment at this time.


Women's FA Cup holders Chelsea will begin the defence of their trophy at Doncaster Rovers Belles.

The fifth-round tie on 20 March comes four days before Chelsea start their Women's Super League One title defence at the Yorkshire club.
Last season's losing finalists Notts County face Durham, while Liverpool host WSL 1 rivals Manchester City.
At least one side from the third tier is guaranteed a sixth-round spot, with Sporting Club Albion away at Brighton.
Sporting Club Albion, who are sixth in the Northern Premier League, are the lowest-ranked side left in the competition after overcoming WSL 2 side Sheffield FC in the fourth round, while Brighton beat Blackburn to progress.
Birmingham City and Arsenal meet in the only other all-WSL 1 tie, while Yeovil Town host top-flight side Sunderland after overcoming Birmingham City on penalties.
The Women's FA Cup final will again be played at Wembley in May. A competition-record crowd of 30,710 watched the 2015 final when it was played at the national stadium for the first time.
Women's FA Cup fifth-round draw
Birmingham City v Arsenal
Doncaster Belles v Chelsea
Brighton & Hove Albion v Sporting Club Albion
Reading v Millwall Lionesses
Yeovil Town v Sunderland
Liverpool v Manchester City
Notts County v Durham
Aston Villa v Everton


Kim Jong-il was one of the world's most reclusive and enigmatic leaders, presiding over a secretive and internationally isolated country.

The world's only hereditary communist ruler, he was criticised for flagrant human rights abuses and for threatening the stability of the region by pursuing a nuclear weapons programme and testing long-range missiles.
When he assumed power after the death of his father, Kim Il-sung, in 1994, very little was known about Kim Jong-il. He had seldom been seen in public.
He was said to have personally ordered the shooting down of a South Korean airliner in 1987.
The South Korean media portrayed him as a vain man, a playboy with a bouffant hairstyle and sporting platform shoes in order to appear taller.
Anecdotal evidence suggests he was not as stupid as his southern neighbours made out, though his over-fondness for food and drink was probably true.
Konstantin Pulikovsky, a Russian emissary who travelled with Mr Kim by train across Russia, reported that the North Korean leader had live lobsters air-lifted to the train each day which he ate with silver chopsticks.
The two men, he said, shared champagne with a bevy of female companions of "utmost beauty and intelligence".
He was seen draining 10 glasses of wine during his 2000 summit with then South Korean President Kim Dae-jung and is known to have a taste for Hennessy VSOP cognac.
Those who met him say he was well-informed and he was said to have followed assiduously international events.
Some saw him as a clever manipulator, willing to take risks to underpin his regime.
Former US Secretary of State Madeleine Albright said that Kim Jong-il was "very much on top of his brief".
His image in North Korea was one of a hero in the typical manner of the dictator's cult of personality.
Official North Korean accounts say he was born in a log cabin and the event was reportedly marked by a double rainbow and a bright star in the sky.
They say he wrote six operas in two years and designed one of Pyongyang's most famous landmarks.
In fact, according to outside experts, Mr Kim was born near the Russian city of Khabarovsk where his guerrilla father was receiving Soviet military support.
Subsequently, the young Kim spent the Korean War in China.
Like most of North Korea's elite, he graduated from Kim Il-sung University.
In 1975, he acquired the title Dear Leader and five years later joined the Central Committee of the Korean Workers Party and was given special responsibility for art and culture.
In 1978, he ordered the abduction of a South Korean film director, Shin Sang-ok and his actress wife Choi Eun-hee.
They were held separately for five years before being reunited at a party banquet.
They said afterwards that Mr Kim had apologised for the kidnappings and asked them to make movies for him. They completed seven before escaping to the West in 1986.
Kim Jong-il's love of the cinema bordered on the obsessive. He is said to have collected a library of 20,000 Hollywood movies and to have even written a book on the cinema. Elizabeth Taylor was believed to have been his pin-up.
He is also believed to have visited the state film company hundreds of times and produced a patriotic 100-part serial on North Korean history.
In 1991, he was elected supreme commander of the Korean People's Army. Analysts believe he was given the position to counter potential resistance to an eventual succession.
By now, North Korea's rigid centrally-controlled economy had slipped into an ever-deepening economic crisis exacerbated by the collapse of the country's main trading partner, the Soviet Union.
Trade dried up and the regime even ran out of fuel for factories and offices.
Natural disasters led to crop failures and hundreds of thousands are believed to have died. Potential unrest was quashed by the authorities.
This grave state of affairs continued after Kim succeeded his father on his death in 1994. However, Kim Jong-il did relieve the crisis somewhat by appealing for international assistance, particularly from China.
He also visited China several times, and was known to be interested in how communist China had adapted its socialist principles to a market economy.
After visiting Beijing and Shanghai in 2000 and 2001, North Korea began experimenting, on a small scale, with private entrepreneurship.
He also moved some way to improving relations with South Korea.
In June 2000, he met the South's leader, Kim Dae-jung, the first inter-Korean summit since the Korean War in 1953 which divided the nation.
The summit's main achievement was to increase links between the states, including allowing the reunion of families separated by the Korean War. More than a million Koreans were affected in this way.
In August 2008 a report appeared in a Japanese news magazine claiming that Kim Jong-il had died in 2003 and that his supposed public appearances had, in fact, been undertaken by body doubles.
A month later US intelligence sources claimed Kim had suffered a stroke, following reports that he had failed to appear at a military parade to mark the country's 60th anniversary.
Amid rumour and counter rumour the North Korean authorities released a video in April 2009 which claimed to show Kim making official visits to factories during November and December 2008.
He made a dramatic appearance in August 2009 when former US President, Bill Clinton, flew to North Korea to secure the release of two American journalists, who had been arrested after allegedly illegally entering North Korea in March.
After meeting Mr Clinton it was reported that Kim Jong-il had agreed to pardon the two journalists and they returned to the United States.
Kim Jong-il's devoted commitment to his father's particular Marxist-Leninist vision was fundamental.
His insistence on maintaining the North's nuclear weapons programme in the face of international criticism, and the development and testing of long-range missiles capable of hitting American cities, cast Kim Jong-il as both a pariah and a maverick, and ensured that his country remained isolated.
His death at the age of 69 on 17 December 2011 was announced on state television.


The outlook for eurozone growth is "more optimistic", the head of the European Central Bank (ECB), Mario Draghi, has said.

Accordingly, the central bank has raised its economic growth forecasts for this year and next, to 1.8% in 2017 and 1.7% in 2018.
That compares with previous forecasts of 1.7% and 1.6% respectively.
The comments came as borrowing costs were kept on hold in the 19-nation bloc, despite a pick-up in inflation.
It currently stands at 2%, which is slightly above the ECB's target of just below 2%. The bank also raised its annual inflation forecast for this year and next to 1.8% and 1.7%.
"I would say the risks of deflation have largely disappeared," Mr Draghi said at a news conference.
The main interest rate remained at 0% and the central bank's bond-buying programme, aimed at boosting the economy, was also kept unchanged.
The bank is currently committed to continuing its bond-buying programme until at least December, although the â‚¬80bn-a-month quantitative easing (QE) scheme will be trimmed to â‚¬60bn a month from April.
Asked at the news conference whether interest rates were likely to rise before the end of the QE programme, Mr Draghi replied that policy makers wanted to see "a sustained adjustment in the rate of inflation, and we don't see it yet... we see progress in the recovery [but] it's a gradual process".
In a statement ahead of the news conference, the ECB had reiterated: "The governing council continues to expect the key ECB interest rates to remain at present or lower levels for an extended period of time, and well past the horizon of the net asset purchases."
However, Mr Draghi said that a sentence had been removed from his introductory statement to the news conference to signal that "there is no longer that sense of urgency in taking further actions... that was prompted by the risks of deflation".
Neil Wilson, an analyst at ETX Capital, said: "Deflation is no longer the concern for the ECB - prices are not rising fast enough to warrant tapering or higher rates, but the imminent risk of deflation has passed.
"That's something of a watershed moment - the end of the beginning in terms of unconventional monetary policy tools perhaps."


Iran flew an unarmed drone over a US aircraft carrier and took "precise" photographs during a naval drill in the Gulf, its state broadcaster said.

Images purporting to show an unnamed US warship were shown on television.
Iran's navy commander praised the operation for getting so close to a warship "to get such accurate footage of the combat units of foreign forces".
The US said an Iranian drone had flown over one of its carriers recently, but did not say if it was this incident.
It had not posed a risk to the USS Harry S Truman, but the move was "abnormal and unprofessional", Reuters news agency quoted a US navy spokeswoman as saying.
Nicole Schwegman said that incident had occurred on 12 January, which is the same day Iran briefly detained 10 US sailors who had entered Iranian territorial waters by mistake.
The report by Iran's state Irinn news channel did not say when the surveillance drone had made its flight except to say it was on the third day of a naval exercise.
The Associated Press news agency said this suggested it had happened on Friday, as Iran's naval drill began earlier this week.
An Iranian light submarine also closely participated in the surveillance operation, Iran's state-run Irna news agency reported.
Adm Habibollah Sayyari, Iran's navy chief, told state TV it was a sign of the "bravery, experience and the scientific capabilities of our drone operators".
International sanctions against Iran over its nuclear programme were lifted this month, somewhat easing its relations with the West.
But within a few days, the US had imposed new sanctions related to Iran's ballistic missile programme.
Iran said the sanctions, which prevent 11 entities and individuals linked to the programme from using the US banking system, had "no legal or moral legitimacy".


Illegal traveller sites are not being dealt with effectively by police and councils, according to two MPs.

Conservatives Robert Halfon, MP for Harlow, and Thurrock's Jackie Doyle-Price have written to government ministers outlining their concerns.
Chief Superintendant Sean O'Callaghan, of Essex Police, said action had been taken where appropriate.
Harlow and Thurrock councils said they had been doing all they could to deal with illegal sites.
Harlow has seen 68 unauthorised sites set up in the last year - a problem "echoed in Thurrock", the MPs said in their letter to the Home, Communities and Justice secretaries.
They claimed Essex Chief Constable Stephen Kavanagh had failed to uphold the law and deal with the issue effectively.
The MPs also criticised the force's crime commissioner (PCC) Nick Alston for "his failure to represent the views of residents in Essex".
Mr Halfon told BBC Essex his constituents had been complaining about anti-social behaviour and the rubbish left behind by travellers.
"The police commissioner, instead of being a poodle for the police's bureaucracy, should be a bulldog for residents of Harlow and Essex," Mr Halfon told BBC Essex.
He called for a zero-tolerance policy on anti-social behaviour, adding that authorities should use "all laws available" to move illegal travellers on.
PCC Nick Alston said he had been involved in several public meetings about the issue, and held regular discussions with the chief constable.
He added it was crucial the situation was dealt with "proportionately and fairly".
Ch Supt O'Callaghan told BBC Essex the sites were assessed on an individual basis and visited regularly by officers.
Harlow Council said it was doing all it could "within the constraints of current legislation".
A Thurrock Council spokesman said action had been taken to remove travellers who were in breach of planning law.


Middle-aged people are being urged to walk faster to help stay healthy, amid concern high levels of inactivity may be harming their health.

Officials at Public Health England said the amount of activity people did started to tail off from the age of 40.
They are urging those between the ages of 40 and 60 to start doing regular brisk walks.
Just 10 minutes a day could have a major impact, reducing the risk of early death by 15%, they say.
But PHE estimates four out of every 10 40- to 60-year-olds do not even manage a brisk 10-minute walk each month.
41%
Do not manage one brisk 10 min walk per month
1 in 6
Deaths linked to inactivity
15% Reduction in risk of early death from at least one brisk 10 min walk per day
20% Less active than we were in the 1960s
15 miles Less walked a year on average than two decades ago
To help, the government agency is promoting a free app - Active 10 - which can monitor the amount of brisk walking an individual does and provide tips on how to incorporate more into the daily routine.
PHE deputy medical director Dr Jenny Harries said: "I know first hand that juggling priorities of everyday life often means exercise takes a back seat.
"But walking to the shops instead of driving, or going for a brisk 10-minute walk on your lunch break each day, can add many healthy years to your life."
Maureen Ejimofor, 44, started taking regular walks three years ago in a bid to improve her health.
At the time, she weighed 18 stone and wanted to make a change. Within seven months, she had lost nearly five stone.
She joined a local organised walking group in Kent and loved it so much she ended up becoming a walk leader in charge of taking groups of people out at the weekend.
She has been using the Active 10 app and encourages others to do the same, describing it as "really useful" in persuading users to get a "burst" of brisk walking into their day.
Another walking fan is Liam Quigley, who has just turned 60.
"My parents used to take us out walking all the time," he says.
"But unfortunately as I got older, I got a taste for the finer things in life, so I used to drink quite a bit, eat some of the wrong stuff. I actually put a lot of weight on.
"I like walking, and I decided to do something about it."
Mr Quigley joined Stockport Walkers and now takes 10-mile hikes.
"Since I joined, I've lost two stone. It's had a good effect on me," he says.
GPs are also being encouraged to get their patients walking faster - defined as a walk of at least 3mph that leaves you breathing faster and increases your heart rate.
Dr Zoe Williams, of the Royal College of GPs, said: "Every GP should talk to their patients about the benefits of brisk walking and recommend the Active 10 app."
PHE is focusing on those in middle age, because of the drop in activity levels.
It is recommended that people do 150 minutes of activity a week, but nearly half of those aged 40 to 60 fail to achieve that and one in five does less than 30 minutes.
While a daily 10-minute brisk walk will not get them to the recommended level, it will be enough to start making a difference to high blood pressure, diabetes, weight issues, depression and anxiety and musculoskeletal problems such as lower back pain.
PHE also hopes by getting this age group active it will have a knock-on effect among those who have children.
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A man who used Facebook to groom a 15-year-old girl who was later raped and murdered has been found guilty of false imprisonment.

Luke Harlow, 28, of Ibstock, Leicestershire, admitted grooming and sexually touching Kayleigh Haywood but had denied taking her captive.
Stephen Beadman, 29, who admitted raping and murdering Kayleigh, was found guilty of imprisonment on Monday.
Both men are due to be sentenced at Nottingham Crown Court on Friday.
More on this story and other news in Leicestershire
Kayleigh's body was found in a field, five days after she was dropped off outside Ibstock Community College, on Friday 13 November.
Her family thought she was joining a friend but she was actually meeting Harlow, who had been grooming her through social media and text messages.
Kayleigh, from Measham, was given "substantial amounts of alcohol" and "sexually touched" by Harlow, according to the prosecution, on that Friday evening.
The following day, Beadman arrived at the flat and the jury agreed Kayleigh was kept prisoner by both men between about 21:00 BST and 03:00 the next morning.
Speaking outside court after the final verdict, Kayleigh's parents said they were "heartbroken and devastated".
"Our hearts have been torn apart," they said in a statement.
"We ask ourselves every day, why? Why Kayleigh? Why did this happen to our beautiful daughter?
"Today, we have got justice for our beautiful daughter. But that doesn't change anything for us. We have to live with this heartache forever.
"The public have been and continue to be a great support and comfort to us, and we want to thank each and every one of you."
The court heard how Harlow became Facebook friends with Kayleigh just two weeks before her death.
He had more than 2,200 friends on Facebook, and police believe many of these were girls and young women he was trying to groom.
He admitted two charges of attempting to meet children following sexual grooming, in relation to two other 15-year-old girls he tried and failed to meet.
Janine Smith, Chief Crown Prosecutor at CPS East Midlands, said Kayleigh suffered "a terrifying ordeal" at the hands of Beadman, but was only in that position because she had been groomed by Harlow before being kept against her will.
"Beadman callously raped and took the life of an innocent teenage girl," said Ms Smith.
"Harlow pursued a succession of underage girls in a sinister manner, talking about 'kidnapping' them and making them 'slaves'.
"I would like to offer my heartfelt sympathy to Kayleigh's family and I hope the conviction of these highly dangerous men will in some way help them start to cope with their loss."
The NSPCC said the "shocking" case was a "stark reminder of the dangers that young people face on social media" - and called for more resources to help police tackle the problem.
"Last week, the NSPCC revealed that more than 3,000 sex crimes using the internet were committed against children last year, and Kayleigh's tragic death is an example of the way the online world is increasingly being used by abusers," an NSPCC spokesman said.
"In the coming years, it is vital that police are given the resources to tackle this rapidly developing, 21st century crime, and that we continue to help our children stay safe online."
Paul Burnett, independent chairman of the Leicestershire and Rutland Local Safeguarding Children Board, said a serious case review is under way "to see if any lessons can be learned and action taken".
31 October - Luke Harlow begins grooming Kayleigh Haywood on Facebook, sending her a message reading: "Hey, how's it going?" Further electronic messaging, which she kept from her parents, then takes place on Facebook and WhatsApp.
13 November - Kayleigh's father drops her off outside Ibstock Community College at about 18:00 GMT, after she agrees to spend the weekend at Harlow's home in George Avenue, Ibstock. At Harlow's request, Kayleigh tells her parents she is staying with a friend.
14 November - Kayleigh speaks to her parents on her iPhone in the morning. At about 21:00, Kayleigh's mobile phone ceases to send messages to her friends.
15 November - Between 03:00 and 03:30 a witness sees a young woman being pinned to the ground by a man who is wrongly assumed to be a policeman because of a reflective strip on his coat. A loud frightened scream of "mummy" is heard by another witness as Kayleigh is attacked by Stephen Beadman and then killed on farmland.
At about 9:30 Kayleigh's smashed iPhone is found on a main road near the defendants' homes. A passerby who finds the handset uses the Sim card to dial the last number called and gets through to a friend of Kayleigh, who in turn contacts the schoolgirl's mother. Kayleigh is then reported missing.
16 November - Detectives arrest Harlow and Beadman in connection with Kayleigh's disappearance as officers search for her on parkland and at a property.
17 November - Police appeal for anyone with information or sightings of the schoolgirl to come forward. Later the same day, Kayleigh's parents - Stephanie Haywood and Martin Whitby - make an emotional appeal through police for her to come home.
18 November - Leicestershire Police announce that officers are treating the disappearance of Kayleigh as murder after finding items of clothing they believe belonged to the teenager in Ibstock and Diseworth. Police find Kayleigh's body in undergrowth near a stream at about 22:00.
19 November - Leicestershire Police charge Beadman, then aged 28, with the murder of Kayleigh Haywood. Harlow, 27, is accused of grooming and two counts of sexual activity with a child.


Radiation levels around tanks storing contaminated water at Japan's crippled Fukushima nuclear plant have risen by a fifth to a new high, officials say.

Ground readings near one set of tanks stood at 2,200 millisieverts (mSv) on Tuesday, the plant operator and Japan's nuclear authority said.
Saturday's reading was 1,800 mSv.
Last month, plant operator Tokyo Electric Power Company (Tepco) said it had found highly contaminated water leaking from a storage tank.
Other leaks have also been reported, prompting the government on Tuesday to pledge 47bn yen ($473m, Â£304m) in funding to tackle the problem.
The spike in radiation levels found on Tuesday was in the same area where the 1,800 mSv level was detected on Saturday, a spokeswoman from Tepco told Bloomberg.
The readings are thought to be high enough to provide a lethal radiation dose to someone standing near contaminated areas without protective gear within hours.
But Japan's Nuclear Regulation Authority (NRA) also said the areas were easily contained.
The earthquake and tsunami in March 2011 knocked out cooling systems to reactors at the Fukushima plant, three of which melted down.
Water is now being pumped in to cool the reactors, but storing the resultant large quantities of radioactive water has proved a challenge for Tepco.
The process creates an extra 400 tonnes of contaminated water every day, which must be stored in temporary tanks.
But leaks of contaminated water, both from the tanks, pipes and through damaged structures, have been a persistent problem. Groundwater from the hills surrounding the plant also flows down and into the radioactive areas.
Under the government plan announced on Tuesday, a wall of frozen earth will be created around the reactors using pipes filled with coolant. This aims to prevent groundwater coming into contact with contaminated water being used to cool fuel rods.
Water treatment systems would also be upgraded to tackle the build-up of contaminated water, officials said.
On Wednesday, Japanese Prime Minister Shinzo Abe told journalists in Tokyo that the government was willing "to take drastic measures of a maximum scale" to resolve the issue ahead of the 2020 summer Olympic Games.
"We are aware of concerns over the issue of contaminated water leakages at Fukushima, the government will take charge and will definitely resolve this problem," he said.
Tokyo is a candidate as a host nation for the Olympics, and the decision is expected in days.


An Israeli air strike has killed a commander from the militant Palestinian Islamic Jihad group in the Gaza Strip.

An Israeli missile hit the car of Ismael al-Ismar, a leader of al-Quds Brigades in the city of Rafah, close to the Egyptian border.
Shortly afterwards, mortars were fired from northern Gaza into southern Israel. There were no injuries.
Violence between Israel and militants in Gaza has flared since a deadly attack on Israeli buses last week.
The Israeli military said its target in Wednesday's attack had been an activist implicated in weapons smuggling and militant operations in Egypt's Sinai region.
The BBC's Yolande Knell in Jerusalem says these exchanges threaten to undermine the informal ceasefire agreement that was announced by an official from Hamas, which governs Gaza, late on Sunday.
This was joined by smaller militant groups.
Al-Quds Brigade is the armed wing of the Islamic Jihad organisation.
On Monday, the Popular Resistance Committees (PRC) - agreed to halt rocket fire against Israel as a "temporary" measure "for the sake of the Palestinian people".
Earlier, Israel's army radio reported that Israeli Prime Minister Benjamin Netanyahu's security cabinet had decided the military would stop its air strikes on Gaza if militants there halted their attacks.
Tensions rose rapidly after a series of shooting ambushes near the Red Sea resort of Eilat last Thursday, which killed eight Israelis.
Israeli Defence Minister Ehud Barak said the attackers had originated in the Gaza Strip, although that is disputed, including by Egyptian officials.
The leader of the PRC, which Israel blamed for the attack was among 15 Palestinians killed in subsequent air raids in Gaza.
Militant groups there responded by firing more than a hundred rockets and mortar shells at Israeli towns and cities.  One man was killed.
1 September: This story was amended to clarify that the origin of the Sinai attackers is disputed.


Norwich City have signed Falkirk midfielder Conor McGrandles for an undisclosed fee.

The Bairns say they have received a club record fee for the 18-year-old, reportedly worth up to £1m.
McGrandles played 66 games in the Scottish Championship and has signed a three-year deal with the Canaries, with the option of a further 12 months.
"It feels brilliant to be here, a dream come true really. I never expected it to happen so quick," he said.
City's first-team coach Gary Holt is a former boss at Falkirk and managed McGrandles for 14 months.
"He was a big factor in me coming here. He told me all about the place and sold it really well," he said.
Norwich boss Neil Adams added: "He's a dynamic, combative player who can be used anywhere across the midfield, and he's already played plenty of games so he has the ability to compete at senior level."


Cristiano Ronaldo scored twice as Real Madrid held on to beat Valencia 3-2 and keep their La Liga title hopes alive.

Real's victory moved them into second place with one game to go, still one point behind leaders Barcelona, who routed Espanyol 5-0.
Atletico Madrid's 2-1 loss at Levante means only Real and Barca can prevail.
Ronaldo's goals either side of a Karim Benzema strike made it 3-1, but Andre Gomes' goal added to Rodrigo's earlier effort to make it a nervy finish.
Relive how the title race developed
Defending champions Barca will take the title if the teams finish level on points thanks to their superior head-to-head record.
Ronaldo took his goal tally for the season to 49 with two excellent finishes, firing low into the net from 20 yards with his right foot to give Real the lead half-way through the first half.
After Rodrigo had pulled one back early in the second half, Ronaldo then restored Real's two-goal advantage as he ran clear to beat Diego Alves with a left-foot shot.
The hosts' cause was aided when goalscorer Rodrigo was dismissed on 83 minutes.
Barcelona have the destiny of the title in their own hands but should they drop points at Granada, Real will secure their first championship since 2012 with a win at Deportivo de La Coruna.
Deportivo would still have been in relegation danger going into the last day but for a 2-0 win at Villarreal on Sunday.
However, that was only their second league win in 21 games.


A Tunisian court has sentenced a British DJ to a year in jail after he played a dance remix of the Muslim call to prayer.

The DJ, known as Dax J, was charged with public indecency and offending public morality.
He has already fled the country, and made a public apology.
The nightclub was shut down after footage of the weekend's event was shared on social media and sparked outrage.
A court spokesperson told AFP news agency that the court dismissed charges against the nightclub owner and an event organiser, but the prosecution has appealed saying the two should have checked what the DJ would be playing.
The event was part of Orbit Festival in Nabeul in the country's north-east.
The footage showed clubbers dancing to music played by two European DJs.
The music included a dance version of the call to prayer, the religious act that Muslims perform five times a day.
"We will not allow attacks against religious feelings and the sacred," the governor of Nabeul, Mnaouar Ouertani, said when the club was shut down.
Earlier in the week, the organisers of the Orbit Festival apologised in a post on the event's Facebook page, but said that they did not accept responsibility for the playing of any offensive music.
The DJ "did not realise it might offend an audience from a Muslim country like ours," they said in the post (in French).
Dax J has offered his "sincere apologies to anyone who may have been offended by music that I played at Orbit Festival in Tunisia on Friday".
"It was never my intention to upset or cause offence to anybody," he said.


Soon after he took the helm at drinks giant Diageo, Paul Walsh played an unusual trick in meetings.

The former chief executive used to pretend that he wasn't the boss, instead asking others what decision needed to be taken and who was going to take it.
His staff looked at him in amazement, having been under the assumption that he would.
"I'd say, 'I'm not capable of taking that decision. You know you should be taking that decision.'"
The approach, he explains, was an attempt to cut through "some of the bureaucratic noise"  and make sure that people were confident enough to speak up and question things when they had more knowledge than him.
"Sometimes the boss doesn't have all the right answers and has to modify their position. In the face of compelling evidence that's what should happen," he says.
As head of a multinational firm, operating in several different countries and employing thousands of staff, Mr Walsh's decision to delegate during his 13 years as chief executive seems eminently sensible.
But of course it only works if a firm has the right senior staff in place. Mr Walsh, now chair of catering giant Compass, says he has always looked for people that he thought would make the right decisions when under pressure.
"I expect capability, but I also want character. I consider this notion of a moral compass very, very strongly," he says.
Leadership expert Steve Tappin says recruiting the right top team is an area many chief executives spend a lot of time on because "the future of the company depends on getting this right".
But for chief executives, letting go of the reins when they've worked their way to the top isn't always easy.
After all, to get there in the first place will have required a certain amount of assertiveness and aggression, or even narcissism, not easy characteristics to subdue.
John Mackey, founder and co-chief executive of supermarket chain Whole Foods, likens the seductive dangers of being in charge to the ring of power featured in JRR Tolkien's fictional trilogy The Lord of the Rings.
"Chief executives have to be able to wear the ring of power and not have this need to be elevated above all else as if they were gods of some kind," he says.
He admits it's difficult, particularly for people at the top who will often have others telling them how great they are, and with their usually large salaries helping to boost their sense of self-importance.
Whole Foods has designed both its management structure and its pay to safeguard against these sorts of dangers.
Mr Mackey already shares the top job with Walter Robb, but the two of them are also part of seven member executive team. These senior staff all receive exactly the same salary, bonus and stock options as the two chief executives, and their salaries are capped at 19 times the average pay of a full-time worker.
Changes in how the firm is run are only made if the whole group agrees on them.
"Walter and I may be the leaders of that group but we all are working together," he says.
But this teamwork only works if all the team members understand exactly what they're working towards.
Joe Plumeri, the former chief executive and chairman of global insurance broker Willis, describes it as "building grandma's house".
In his 12 years at the head of Willis, he successfully returned it from private to public ownership and led its $2.1bn purchase of Hilb Rogal & Hobbs, one of the largest insurance brokerage deals of the last decade.
But when the American arrived as chief executive with his new ideas for the business, it proved a bit of a culture shock for the staff at the 200-year-old British company.
He said people looked at him as if The Fonz, the character in the US sitcom Happy Days, had turned up to lead the firm.
"I had a dream of a different company and a different era that wasn't the one that insured the Titanic," he says.
To get people to see his view for the firm's future, he used his "grandma's house" trick, which he likens to parents who build an exciting picture of ice cream, toys and cake in order to keep their children entertained on long car journeys, for example to see their grandparents.
"You've got to be able to paint a picture of a vision of where a company is going that is better than where they are now and the reason you do that is to get them to endure the trip because when they come to work every day they're going to have to do things that are different.
"They'll do all of that as long as they know where grandma's house is," he says.
This feature is based on interviews by leadership expert Steve Tappin for the BBC's CEO Guru series, produced by Neil Koenig.


Three years after what he describes as "the worst experience of his life", athlete Rhys Williams wants one last chance to represent his country.

That would be at the Commonwealth Games at the Gold Coast next April. If he achieves this goal Williams, 33, will then hang up his spikes.
Then, and maybe only then, Williams will be able to reflect more fondly on a period of time where he has fretted over money, suffered with stress and felt the need to temporarily move his life to the other side of the world.
The Commonwealths would be a fitting end because of what happened to Williams when he missed Glasgow 2014.
The former European 400m hurdles champion had to withdraw on the eve of the Games, along with 800m runner Gareth Warburton, after testing positive at a Grand Prix in Glasgow.
The pair were cleared by UK Anti-Doping (UKAD) of knowingly cheating but Williams received a four-month ban, while Warburton was handed a six-month suspension after the pair took supplements they didn't know were contaminated.
Williams has battled back and just failed to reach the Olympics last year after his selection credentials were ignored by British Athletics.  Now he wants to complete his career in a Welsh vest.
The Commonwealth Games is an event where Williams won a bronze medal in Delhi in 2010 behind fellow Welshman Dai Greene and he was supposed to be the athletics co-captain in Scotland three years ago before his withdrawal.
"I would love to be in that Welsh team and finish my career on a happy note," Williams told BBC Wales' Beth Fisher in a special radio interview.
"If I don't, then it's not meant to be but it won't be from a lack of trying. I am very proud to be Welsh.
"It's been a long career and I have enjoyed it. There have been some been downs and some great ups.
"I had a massive setback in 2014, the worst experience of my life.  I believe in fate and things do happen for a reason.
"I learned a lot, who you true friends are.
"I am 33 now. I wanted to finish after that Commonwealth Games (in Glasgow) because I have other goals in life.
"But what happened there has kept me going."
Williams admitted the road back on track following the verdict to his case in 2015 has been fraught.
The athlete admitted he had struggled with the financial implications of his legal case following the failed doping test which was helped to be funded by his father and former Welsh rugby player JJ Williams.
Williams says the event had taken its toll on the family.
"We went for a top QC and had a great result with a four-month suspension," said Williams.
"Luckily my Dad was in a position to help me financially and he offered and decided to go down the route of getting a top QC.
"You are left with a massive debt. It cost us all a fortune and you have to pay it.
"I am lucky but there is bad feeling over the money side, not necessarily with the other stuff, between me and my Dad.
"Money can sometimes cause a lot of headaches and it caused my Dad a lot of headaches.
"Put yourself in his shoes. His son was getting married and he was very helpful with putting some money towards that.
"He has worked hard for his money so why should he give it to me?"
Following the verdict, Williams admitted he initially struggled to cope with the aftermath and relocated to Australia with wife Leila for a time.
"I suffered from stress afterwards," admitted Williams.
"I was a shell of myself. The sports psychologist referred me to a clinical psychologist so I tried to sort the problem out.
"It was stressful for everyone who was associated with me. So we went to Australia to get away from it all, a change of scenery and get a bit of sun.
"It worked. At the end of the year I was ranked second in the UK, finished fifth in the European Championships and only just missed out on the Olympics.
"It was hard. But with hard work we managed to get ourselves out of this bad situation."
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Back on the track last year, Williams returned close to his best still had to cope with the disappointment of his Olympics omission last year which he unsuccessfully appealed.
This was despite Williams, who reached the London 2012 semi-finals, running two Olympics qualification times and finishing fifth at the European Championships in Amsterdam.
There was a spot available, with only Seb Rodger and Jack Green named in the event, but the selectors chose not to fill the third space despite Williams finishing third in the British Championships and Olympics Trials.
Despite that setback Williams has his eyes on that one final flourish with Wales, as well as helping other athletes about checking their supplements.
"It is very much a taboo subject but not to me," said Williams.
"I am on the British Athletics anti-doping sub committee and I have given lots of talks.
"I want to turn my experience as a positive for others so they don't have to go through what I went through."


German firm Siemens says it will make an offer for France's Alstom if it can see the company's books.

The engineering firm wants access to Alstom's "data room" and "permission to interview the management" for four weeks as a prerequisite for an offer.
On Monday, Siemens officials met French President Francois Hollande to discuss a possible deal.
The news follows reports that General Electric (GE) wants to buy Alstom, which makes TGV high-speed trains.
On Sunday, French newspaper Le Figaro reported that Siemens wanted to offer Alstom half its trainmaking business and some cash.
In return, Siemens wants Alstom's energy industry turbines business, according to the report.
Mr Hollande and senior French ministers met General Electric and Siemens on Monday in separate meetings.
The politicians wanted "to make sure that French companies... do not become prey," France's economy minister Arnaud Montebourg said.
Nevertheless, France is "open to alliances that help to equip [it] for globalisation", he said.
Siemens chief executive Joe Kaeser also met Mr Hollande and Mr Montebourg, and described the meeting as an "open, trustful and amicable exchange".
Alstom has about 93,000 employees in 100 countries around the world, and employs about 18,000 people in France.
The engineering giant had to be bailed out by the French government in 2004, and has suffered heavy debts and a fall in orders over the past decade.


A man has died after suffering serious head injuries at a pub in Rochdale.

Police found the 28-year-old injured at the Mucky Duck on Drake Street just after midnight. He was taken to Bury's Fairfield Hospital where he later died.
A police spokesman said it was believed he had been assaulted but it was not yet known if the attack took place inside or outside the pub.
Two men have been arrested in connection with the man's death and remain in police custody.


The Irish government has been criticised for failing to adequately protect the human rights of vulnerable groups during the recession.

The Irish Human Rights and Equality Commission said seven years of austerity resulted in the burden of the crisis falling disproportionally on those least able to bear it.
The commission was set up last year to promote and protect human rights in the state.
This is its first report.
Speaking on RTÃ‰'s Morning Ireland programme, Chief Commissioner Emily Logan said the government had failed to meet basic human rights standards required under international law - in the stark choices made during the recession.
There was an absence of any human rights or equality assessment of the "troika" (EU, IMF and European Central Bank) bail-out programme.
This meant those who were already disadvantaged were even more susceptible to unemployment, lower incomes or poorer living standards.
People with disabilities experienced the impact of austerity measures more acutely, with the rate of unemployment almost trebling among this group - from 8% to 22% during the recession.
The report, published on Thursday, comes ahead of a UN Committee in Geneva next week where Ireland will be asked to defend its record on human rights.


The Republic of Ireland is to take in at least 1,800 refugees amid growing public outcry over the tens of thousands of people fleeing to Europe.

This trebles original plans to accept 600 refugees over the next two years.
The increase was announced two days after images emerged of three-year-old Syrian Aylan Kurdi's body washed up on a Turkish beach.
"What we have seen demands the most comprehensive response," said Irish justice minister Frances Fitzgerald.
"We want to respond in as humanitarian a way as possible."
Ms Fitzgerald said if European leaders agree to increase the number of refugees being accepted across the bloc to 150,000, it will effectively treble the Republic of Ireland's commitment to the crisis.
"I believe that is a minimum of the response that we will be making," she told RTE Radio.
Speaking on RTE television, Irish prime minister Enda Kenny suggested Ireland could take in more than 1,800 refugees.
Mr Kenny said that on the basis that the EU was now looking at relocating more than 100,000 refugees from Greece and Italy, then the figure "may be more" than the 1,800.
"Ireland can cope with more than already taken," he said.
Sinn FÃ©in leader Gerry Adams said the move was welcome, but added: "The Irish government must be imaginative and generous in its response to a crisis which has a deep historical resonance for the Irish people."
The Irish government made the announcement as the United Nations high commissioner called for Europe to draw up a common mass relocation plan for 200,000 refugees - the worst crisis of its kind since World War Two.
Germany has already accepted 35,000 vulnerable Syrians through a UN refugee scheme, Canada more than 10,000, Australia 5,600 and Switzerland 3,500.
Germany also expects to take in a total of 800,000 asylum seekers through all routes this year.
Separately, it is expected 3,500 to 4,000 people will seek asylum in Ireland this year. The country has a population of 4.5m and an economy growing faster than the rest of Europe after several years of recession and austerity.


American Sam Querrey is through to the last 16 of Wimbledon, wrapping up his delayed match against Jo-Wilfried Tsonga in just five minutes.

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The match on Court Two was halted for bad light just after 21:00 BST on Friday and when played resumed on Saturday, the 24th seed immediately broke France's Tsonga to win 6-2 3-6 7-6 (7-5) 1-6 7-5.
Grigor Dimitrov is also through after Israel's Dudi Sela retired with injury.
The Bulgarian was leading 6-1 6-1.
Sela lost the first set in 23 minutes before he called for the trainer and then went off court for a medical time-out to treat a leg injury.
He returned 10 minutes later, but retired immediately after 13th seed Dimitrov had won the second set.
Last year's runner-up Milos Raonic of Canada beat Spain's Albert Ramos-Vinolas 7-6 (7-3) 6-4 7-5 to progress to the second week.
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Gael Monfils, seeded 15, suffered a shock defeat by world number 51 Adrian Mannarino.
Monfils had been two sets to one up, but lost the fourth 6-3 and fell away in the final set against his fellow Frenchman, losing 7-6 (7-3) 4-6 5-7 6-3 6-2.
Austria's Dominic Thiem, seeded eighth, comfortably beat America's world number 67 Jared Donaldson, 7-5 6-4 6-2.
German 10th seed Alexander Zverev beat Austrian qualifier Sebastian Ofner 6-4 6-4 6-2.
Tomas Berdych, seeded 11, of the Czech Republic is through after seeing off Spanish veteran David Ferrer 6-3 6-4 6-3.
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Querrey, who knocked out Novak Djokovic on his way to the quarter-finals last year, said: "After such a great match it was a bit of an anti-climax in the end.
"I've been in that situation before (coming out to serve to stay in a match) and it's tough."
Tsonga, the 12th seed, smashed a ball out of the court after the defeat.
"I'm frustrated because I lost and I stayed two minutes on court today," he said.
When he was asked if the match should have been halted on Friday, he replied: "I was OK with that. It's not a problem. If I come and win my game, we continue.
"It's just part of the game. I did what I had to do. Unfortunately it didn't work."
Tsonga had faced a similar fate at the French Open, when his first-round tie against Renzo Olivo was stopped for bad light.
They returned the following day, only for Tsonga to lose after one game.
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Northern Ireland's local newspaper landscape got smaller this week with confirmation that 11 titles are to close with immediate effect.

They include names such as the Armagh Observer, the Dungannon Observer and the Ballymena Chronicle.
Their owner, Observer Newspapers NI Ltd, announced the closures on the front pages of this week's papers, which will be the final editions.
The firm blamed "challenging circumstances" in the industry.
For one veteran journalist, who spent half a century working for Observer Newspapers, the demise of his local paper was "emotional".
Joe McManus, who ran the Armagh Observer virtually by himself from an office in the city, told the BBC it was a vocation, not a job.
"I saw myself more as a servant of the public than a journalist, and I've shared in people's joys and sorrows," he said.
In its last ever edition, the Armagh Observer led with the death of a young swimmer who suddenly became ill during a training session in the city's Orchard leisure centre.
The paper said staff called an ambulance for 20-year-old Christopher Rogers, who was a member of Armagh Swimming Club, but he died later in hospital.
Northern Ireland's latest political crisis may be taking a break over the Easter holidays, but there is no such respite for the crisis in its healthcare system.
Another rural GP practice is shutting its doors because there is no-one willing to replace its retiring family doctor.
The Fermanagh Herald reports that Roslea Medical Practice will close on Saturday, leaving the village without its own doctor for the first time in 170 years.
The paper says that some patients will be forced to make "a 35-mile round trip" just to see a GP.
Councillor Brian McCaffrey tells the paper people are "genuinely angry" about the closure, which would add to the financial worry of patients with poor transport access.
The Herald's lead story is an emotional interview with the "heartbroken" parents of a four-year-old boy who died in a farming accident.
Thomas Magee was struck by a vehicle on their family farm in Maguiresbridge last week.
"I don't know how we will move on from this," his father David said, adding "right now it feels like someone has stuck a knife in our hearts".
In County Down, the Newry Reporter has been keeping a close watch on emergency services at Daisy Hill Hospital, after the Southern Trust warned last month staff shortages have left the service "vulnerable".
At the time, patients were told that if the service was suspended, they would have to travel to Craigavon Area Hospital in County Armagh.
But according to the paper, the health trust had to divert ambulances away from Craigavon last week, due to the "high number" of patients attending its emergency department.
Most of the diverted ambulances were sent to - where else? - the beleaguered Daisy Hill, but the trust said that one patient was taken to Antrim Area Hospital.
The full 999 divert began about 16:00 BST on Monday 3 April and remained in force for over 15 hours, according to the paper.
On a happier note, the Reporter celebrates a Â£50,000 windfall for a Newry-based organisation which supports young people with Down's Syndrome.
Members of the group, Down Right Brilliant, posed for a front page photo after winning public support in the Big Lottery's People's Project.
The Antrim Guardian leads with calls for an investigation into a former children's home after a self-confessed paedophile admitted abusing a boy there more than 40 years ago.
It follows a BBC investigation, which tracked Henry Clarke down to Canada to confront him about child abuse he admitted to police in the 1980s.
He confessed to abusing three boys from different care homes in Northern Ireland, including the now closed Firmount home in Antrim, but was never prosecuted.
The Guardian points out that Firmount was not among the 22 institutions investigated by the Historical Institutional Abuse (HIA) inquiry, "even though a self-confessed paedophile freely admitted that it was one of his hunting grounds".
Elsewhere on its front page, the paper reminds its readers that, as of this week, there will be a new focus to policing in their district.
PSNI officers started wearing Body Worn Video cameras in Antrim and Newtownabbey from Monday 10 April.
Officers say the aim of the new technology is to assist in evidence gathering and accountability.
It is being rolled out gradually across PSNI districts, following a successful pilot in 2014.
In County Tyrone, the Mid-Ulster Mail asks if it will be "third time lucky" for the troubled Desertcreat training college project.
Planning permission for the site was first granted in 2005 and the initial vision was for a multi-agency facility to train police, prison officers and firefighters.
However, the paper notes that the latest planning application is for a facility solely for the Northern Ireland Fire and Rescue Service.
Mid Ulster MLA Keith Buchanan tells the paper he is disappointed that it will not be the "world class" facility first envisaged, but adds it is "still a good boost for the area".
Inside the Mail, pedestrians are warned they are "dicing with death" in Moneymore because the Cookstown Road is not even "up to Third World standard".
The warning comes from Ulster Unionist councillor George Shiels, who is pictured on a bridge with a large, ominous-looking cracked parapet.
"What motorists don't realise is that the road they are travelling on may be in danger of collapsing any moment," the councillor claimed.
But the Department of Infrastructure told the paper the bridge cracks are "historic" and are being monitored by engineers.
The Coleraine Chronicle leads with a heart-warming story about the "remarkable" recovery of a boy who suffered severe brain damage in a road accident.
Ten-year-old Liam McCallum was hit by a car as he got off a bus in January.
His father, Ali, tells the paper: "Liam wasn't meant to survive, his injuries were so bad, but he is stubborn and a real wee fighter and he's making steady progress."
The young football fan still faces months of hospital treatment but is hoping to get out for short breaks, with a school sports day and a trip to the Irish Cup final on the wish list.
It's no holiday camp for Causeway Coast and Glens Council however, which could be facing a "flood of compensation claims" from caravan owners.
The Coleraine Chronicle reports that the council was taken to court after it closed Juniper Hill caravan park over the winter of 2014 in order to carry out "essential" electrical maintenance.
One couple sued the council for damages because they were prevented from accessing their caravan over winter, and won Â£750 in compensation.
Portrush councillor Norman Hillis told the paper he was concerned the ruling could "open the floodgates to further claims".


Paris St-Germain have announced the signing of Uruguay striker Edinson Cavani from Napoli for a reported £55m.

The 26-year-old has signed a five-year contract with the French champions, who are backed by Qatar Sports Investments.
Cavani scored 78 league goals in three seasons with Napoli and finished top scorer in Serie A last season.
"The transfer of Edinson Cavani is further proof of the club's ability to attract the best players in the world," said PSG president Nasser Al-Khelaifi.
"The player was seduced by the club's sporting project and is delighted to be joining an ambitious side, impatient to take on new challenges.
"We are especially happy to present such a hugely coveted player of immense talent to our supporters."
The deal means Cavani is the most expensive transfer in French football history, eclipsing the £50m that Monaco are reported to have paid Atletico Madrid for Colombia forward Radamel Falcao.
He will line up alongside Sweden international Zlatan Ibrahimovic, who was named Ligue 1 player of the year after he scored 30 goals in his debut season in France following his £15.7m arrival from AC Milan.
Cavani,  and also linked with Chelsea and Real Madrid, says he joined Laurent Blanc's side to challenge for major honours.
"I'd like to thank everyone who made this transfer possible, it's a great project," Cavani said.
"I'd also like to thank the people in Napoli who went out of their way to make it possible.
"I come here with lots of joy, lots of confidence, lots of hunger and lots of motivation to win major trophies."


While FA Cup winner Peter Reid is managing Nicolas Anelka and Freddie Ljungberg in the inaugural Indian Super League, his younger, less well-known brother is seeking to make football history of his own this weekend.

Should Shaun Reid steer Warrington Town, who play in the eighth-tier Northern Premier League Division One North, to victory over North Ferriby United, it will be the first time the Yellows have reached the FA Cup first round.
"I've already been on the phone to ask Peter if I can borrow Anelka for the day, but we couldn't get him registered in time," the younger Reid said.
There is a nine-year age gap between the siblings, who spent their playing careers at opposite ends of the professional ladder.
The elder Reid spent most of his career in the top flight at Bolton, Everton, QPR, Manchester City and Southampton, earning 13 England caps along the way.
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Shaun had midfield spells at Rochdale, York, Bury and Chester.
Yet despite the age gap and differing scale of success, the Liverpool-born brothers are close.
When 58-year-old Peter was appointed manager of Plymouth Argyle in 2010, he offered Shaun a coaching job at Home Park.
And since being appointed Warrington manager in 2012, Shaun has reciprocated by inviting Peter - whose managerial CV includes spells in charge of Sunderland and Manchester City - to take training at the Cheshire club.
The brotherly love might surprise those who witnessed the only time the duo faced one another on the pitch, on 13 August 1994.
The team party was at the Royal Lancaster Hotel. Let's just say I had a few shandies. I actually lost my medal at one stage. Adrian Heath's dad eventually found it... in a lift
Peter, whose medal collection also includes two league titles and a European Cup Winners' Cup, had joined fourth-tier Bury in the twilight of his playing career, while Shaun - 28 at the time - was a regular in Rochdale's engine room.
Bury lost a bruising contest 1-0 at Gigg Lane in what turned out to be Peter's only appearance for the Shakers before retirement.
"The tackles were flying and I remember smashing Shaun on one occasion," Peter told BBC Sport.
The younger brother's account is different.
"We were knocking seven bells out of one another right from the off," recalled 49-year-old Shaun.
"I remember the referee pulling us together quite early in the game and saying: 'Lads, you're not giving me a chance here.'"
Shaun was at Wembley to see his brother lift the FA Cup with Everton in 1984, when goals by Graeme Sharp and Andy Gray secured a 2-0 win over Graham Taylor's Watford.
"It was a very proud moment," added Shaun. "I was 19 at the time and I went to the team party after the match. The evening was a bit of a blur.
"There were 20 of us from the family at Wembley... mum, dad, aunts and uncles.
"It's something I will never forget and that's why the FA Cup is a very special competition to me.
"I spent my playing career in the lower reaches of the Football League and didn't go further than the third round.
"So if I can get Warrington to the first round for the first time in their history then it will mean an awful lot to me."
This is Warrington's seventh game in this season's competition.
Saturday's opponents North Ferriby play two leagues above them in the Conference North.
But confidence is high in the Yellows camp after they eliminated Colwyn Bay, also of the Conference North, in the last round.
An FA Cup fourth qualifying round tie at Warrington's 3,500-capacity Cantilever Park is a world away from the glitz and the glamour of the Indian Super League, where Peter is in charge of Mumbai City.
A crowd of 28,000 watched his side hammer Pune City 5-0 last Saturday.
Around 600 - three times Warrington's average - are expected on Saturday to see whether a team made up of solicitors, delivery drivers and postmen can join League One and League Two clubs in the first-round draw.
But the part-time club, that operates in the shadows of the town's successful rugby league side, will be in Peter's thoughts.
"I'll be following Warrington Town's Twitter feed from India," he added.
"I really enjoy going down there and watching the lads play.
"It would be terrific for a club of their size to reach the first round. I've got my fingers crossed they do it."


Scientists are celebrating the 30th anniversary of a unique research project which studies wild sheep living in the remote archipelago of St Kilda.

Their work is focussed on the feral population of Soay sheep on Hirta.
Edinburgh University says the study has enabled ground-breaking discoveries about how Charles Darwin's theory of natural selection plays out in reality.
It has also given insights into how wild animals age and how they are responding to climate change.
Researchers from the University of Edinburgh, the University of Cambridge and Imperial College London have been marking the anniversary at a series of lectures held at the Royal Society of Edinburgh.
Alexander Bennett of the National Trust for Scotland, which was bequeathed St Kilda by the 5th Marquess of Bute in 1957, describes the Soay sheep as emblematic of the islands.
He said: "They've become wild since the islanders themselves were evacuated in 1930 and today the visitors love them.
"But we have to explain to them the importance of this research - the longest running large mammal research project in the world."
Scientists have been intrigued by the way in which the number of Soay sheep on Hirta increases, before falling sharply. This process is repeated at irregular intervals.
Prof Josephine Pemberton of the University of Edinburgh's School of Biological Sciences has been involved in the study since 1985.
She told BBC Scotland News: "The sheep are relatively straightforward to study because they are in a very simple ecosystem.
"They have no competitors for the food and there are no predators.
"You can follow the lives of individuals and in that way you can track what individual events lead them to have these very unusual population dynamics."
High numbers, poor winter weather and demographics all increase the likelihood of a crash in numbers.
A sharp drop in the population is less likely when there are relatively high numbers of mature females - the most resilient group of Soay sheep.
Visitors who have made the long journey to St Kilda often ask why the Soay sheep are much smaller than domestic sheep seen elsewhere.
The scientists believe they have the answer.
Prof Pemberton explained: "They are growing a little more slowly compared with 30 years ago.
"Although we know that small lambs are more likely to die in winter, what's been happening is that as the climate has changed and the winters have got shorter, the little lambs are more likely to survive.
"The consequence of that is that you have these very small animals entering the population and they are bringing down the mean size."
Dan Nussey, a research fellow at the University of Edinburgh, studies the ageing process in wild animals.
He said: "I am interested in establishing what is responsible for the variation that we see in when and how quickly ageing manifests in the Soay sheep and more generally in animal populations.
"There is a very long standing belief in the more mainstream ageing research world that wild animals don't grow old, essentially that nature is too harsh and they don't live long enough.
"What we've seen over the last five to 10 years with the emergence and maturation of long term studies, like the one in St Kilda, is overwhelming evidence that particularly in longer lived birds and mammals we really can see that process."
The research work in St Kilda is seen as internationally important.
Few other populations of large mammals anywhere in the world are studied in such detail.
Similar research is focussed on red deer on the Hebridean island of Rum, bighorn sheep in Canada and kangaroos in Australia.
But after decades of work, the Soay sheep of St Kilda continue to fascinate scientists from around the world who travel to these remote islands to learn more about this unique population and our natural world.


A Kurdish town in Turkey's Diyarbakir province has entered its ninth day under curfew as authorities fight rebels of the Kurdistan Workers' Party (PKK).

Authorities have banned residents of Silvan from leaving their homes as they carry out operations against the youth branch of the group.
At least six people have been killed, according to officials.
The PKK resumed fighting against the army following a unilateral ceasefire.
Three districts in Silvan, which is home to around 90,000 people, have been under lockdown.
One soldier and five rebels have been killed in operations, the Diyarbakir governor's office said in a statement.
A 75-year-old cleric from Silvan - who did not want to be named - told the BBC he had to escape to Diyarbakir, located 85km (52 miles) west of Silvan.
"There are snipers everywhere; we can't get out from our homes. We can't sleep during the night because of all those explosions," he said.
"We hear occasional artillery fire. My house is completely destroyed. I had to move in to my relatives' place," said Mevlude, a resident from Silvan's Tekel district.
Communication lines with the town have been severed.
There have been six separate curfews in Silvan since the PKK declared self-rule of the town in August.
The latest was announced one day after the general election, which the ruling AKP party won with almost 50% of the vote.


Researchers have revealed more detail about the evolutionary "arms race" between bats and moths.

One study in the journal Current Biology has shown how a species of bat uses a quiet "stealth mode" of the clicks it uses to locate its prey.
Another from a Royal Society journal showed that a moth can distinguish between clicks that mean it has been spotted, and clicks that mean a strike.
This allows the moths to choose when to spend energy on defensive measures.
Moths live for just a few days and must evade predators and find a mate, often without eating.
Bats eat a wide array of insects but many species prefer the simple, high-nutrition snack that a moth provides.
They both navigate and hunt by emitting a stream of ultrasound clicks and listening for the echoes in a natural form of sonar, with the clicks repeating faster and faster as the bats close in on prey.
Some moths, upon hearing the clicks, are known to reply with their own high-intensity clicks, or to fly erratically in looping evasive manoeuvres, or even to simply drop out of the sky.
The interplay between bats' strategies to hunt and the moths' strategies to avoid being eaten are frequently cited as a classic example of co-evolution.
"It often seems like predators and prey are going through a contiunous cycle or 'arms race', where each is trying to outwit the other," said Hannah ter Hofstede, the University of Bristol researcher who co-authored the Current Biology study.
"The predator is always trying to capture the prey and that selects for better defences in the prey. Over evolutionary timescales, that causes gradual changes in both groups."
In a strategy that may be a moth-hunting adaptation, some bats are known to use clicks that are at a frequency, or pitch, either above or below moths' hearing ranges.
High-pitched clicks have a larger range, while lower-pitched clicks are absorbed less by the atmosphere It remains unclear whether these pitch-shifting techniques adapted specifically to bypass moth defences or simply to cope in certain environments or situations.
Dr ter Hofstede and her colleagues were able to listen in on the Barbastella bat as it hunted, demonstrating that it had a completely different approach - its clicks were much reduced in volume, becoming even quieter as it closed in on prey.
"It seems like the majority of bats... call very loudly because they need as much information as possible from their surroundings," Dr ter Hofstede told BBC News.
"We're saying that this [low-volume tactic] is an adaptation to get around the moths' defence - it doesn't have any other useful purpose."
While the lower volume of clicks reduces the range over which the bats can successfully hunt, the team showed that the approach leads to Barbastella bats eating significantly higher numbers of the nutrient-rich moths than other, louder species.
Another study by John Ratcliffe of the University of Southern Denmark and his colleagues has shown how one species of moth is taking part in the arms race.
The team played bat clicks to the moths while measuring the impulses along the nerves in their ears, discovering evidence of a seemingly complex cost-benefit analysis.
Firstly, the moths responded differently to higher or lower click rates, showing an ability to discriminate between a bat that has only just noticed and one that is quickly closing in.
What is more, the team found that the "habituation" - the likelihood that after hearing them many times, the calls would elicit a response - was different for the high-risk compared to the low-risk calls.
The explanation is that a moth in a less threatening environment is well served by spending its energy and time avoiding capture when pursued only rarely by a predator. But a moth that finds itself frequently chased cannot spend all of its time diving and clicking, Dr Ratcliffe told BBC News.
"You've got five days to find youself a mate - hopefully a few mates - and if you're constantly being knocked out of the sky by the sound of bats or always producing sounds of really high intensity, you have a problem."
The more highly threatened moth must first and foremost find a mate and so take greater risks, responding less often to the calls of an oncoming predator.
"The moth is doing something more; it's not just 'push a button and the moth puts out a product', the moth is actually assessing and reassessing risks over and over again," said Dr Ratcliffe.
"We've got a bug that's using very little information but they're probably better gamblers than guys in the casino."


Luis Figo has joined Michael van Praag in withdrawing from the Fifa presidential election on 29 May.

Ex-Portugal midfielder Figo, 42, pulled out on the same day as Van Praag, 67, to leave Prince Ali Bin Al-Hussein of Jordan as Blatter's only rival.
Blatter is favourite to win a fifth term as president and Figo said: "This process is anything but an election.
"This process is a plebiscite for the delivery of absolute power to one man - something I refuse to go along with."
Each of Fifa's 209 member associations have a vote in the election and Van Praag, who is president of the Dutch football federation, says he will now support Prince Ali.
The English Football Association also intend to support Prince Ali, while the Scottish FA had previously said they would back Van Praag.
The Dutchman held a joint news conference with Prince Ali in Amsterdam on Thursday, urging his supporters to get behind the Jordanian to unseat Blatter.
"Prince Ali Bin Al-Hussein convincingly demonstrated that at this moment in time he is the candidate who has the biggest chance to challenge Sepp Blatter," Van Praag said.
"It is impossible that Fifa moves on with its current presidency," he added.
Figo also highlighted the need for change in his withdrawal statement.
"I travelled and met extraordinary people who, though they recognized the value of much that had been done, also concurred with the need for change, one that cleans up Fifa's reputation as an obscure organization that is so often viewed as a place of corruption," he said.
"I have seen with my own eyes federation presidents who, after one day comparing Fifa leaders to the devil, then go on stage and compare those same people with Jesus Christ. Nobody told me about this. I saw it with my own eyes."
He also questioned an election process in which a main candidate - Blatter - had not produced a manifesto "so that federation presidents know what they're voting for".
Figo added: "There has not been a single public debate about each candidate's proposals."
The latest withdrawal comes after another presidential candidate, Frenchman Jerome Champagne, a former Fifa deputy general secretary, pulled out in February.
Former Tottenham and Newcastle midfielder David Ginola, backed by a betting company, originally announced his intention to stand against Blatter in January, but withdrew two weeks later.
The vote will be held in Zurich at Fifa's annual congress and requires the winning candidate to secure a two-thirds majority in the first round of voting.
If subsequent rounds are required then a simple majority is all that is required for victory.