Newspaper headlines: Obama on the EU and Mind the Gap man dies
The official start of campaigning ahead of June's in-out referendum is covered in all of Saturday's papers, as they assess the various claims made by the rival camps of the risks or benefits of the UK leaving the EU.
There is also coverage of a potential intervention in the debate by US President Barack Obama, who is due to visit the UK next week.
The Guardian says the president plans to use his time here - which coincides with celebrations for the Queen's 90th birthday - to make the case for Britain's EU membership.
"Obama is seen by Downing Street as the last influential, independent voice yet to be deployed in support of Britain remaining in the EU," says the paper.
The Guardian adds that discussions are continuing as to whether the president should warn about the impact of a Leave vote on US-UK trade. America is Britain's biggest export market outside the EU, says the paper, worth more than $54bn (£38bn) in 2014.
Mr Obama will "bring the power of the presidential bully pulpit" to the debate, says the Financial Times. It also quotes Anthony Wells of pollsters YouGov as saying the president's message could resonate with British voters and they were likely to "pay attention" to his views.
The Times reports that those campaigning for a Leave vote are seeking to "minimise the damage that will be done by the intervention". It quotes leading "Brexit" figure, Conservative MP Liam Fox, as saying that while it was "clearly in the interests" of the UK and US to see a "politically, socially and economically stable European continent", the EU and Europe were not synonymous.
Dr Fox is not the only "Brexiteer" to warn Mr Obama against getting involved, reports the Daily Telegraph, which quotes London Mayor Boris Johnson as saying it was "plainly hypocritical" of the US urge Britain not to "sacrifice control of our laws, our sovereignty, our money and our democracy, when they would never dream of doing the same"
The Sun pulls no punches in its editorial column, saying President Obama has "absolutely no right to stick his nose" into the referendum debate, before denouncing his warnings about the UK's security as "empty fearmongering".
The Daily Mail reports that the head of the Roman Catholic Church in England and Wales, Cardinal Vincent Nichols is also warning against "Brexit", saying such a move would leave the UK facing "more complex problems".
German leader Angela Merkel is coming under fire for agreeing to a Turkish demand to prosecute a comedian who satirised President Recep Tayip Erdogan on TV, reports the Times.
The Guardian explains that German comedian Jan Boehmermann "sat before a Turkish flag and a portrait of Erdogan, reading out a poem that accused the Turkish president of 'repressing minorities, kicking Kurds and slapping Christians'".
Boehmermann justified his poem, says the Daily Telegraph, as a response to earlier efforts by Turkey to censor criticism of Mr Erdogan in the German media.
The paper says Boehmermann could face trial in Germany "under rarely-used legislation against 'insulting a foreign head of state'" after mocking the Turkish leader on the ZDF network.
The Times criticises Mrs Merkel in its leader column, saying her decision "is a retreat from one of the most basic tenets of democracy, freedom of speech" and shows she is dependent on the "autocratic" Mr Erdogan to help resolve Europe's migrant crisis.
The Daily Mail reports that Boehmermann has been under police protection since reading out the so-called "Defamatory Poem" on 31 March, although he had "gleefully admitted" at the time he was flouting Germany's legal limits on free expression.
The Daily Telegraph says that in her statement announcing the prosecution Mrs Merkel "voiced concerns over freedom of speech in Turkey, where several journalists are facing trial in a government crackdown on dissent".
The law which allowed Mr Erdogan's government to request the prosecution is now likely to be scrapped, says the Guardian, with several opposition parties calling for its repeal since the row blew up.
- Tired? You have Americanitis - the Daily Express reveals that a feeling of overwork and constant fatigue is not the scourge of modern-day life we might've thought it was, as a similar condition known as "neurasthenia" or Americanitis was diagnosed by doctors in Victorian times. Treatment for men included doing exercise until they rediscovered their vigour, while women were given up to eight weeks bed rest and banned from reading.
- From As to Zzzzs - sticking with the theme of tiredness, the Sun reports that some secondary school pupils are to get an extra hour in bed to "improve behaviour and exam results". Selected teenagers from 12 schools will take part in the academic study which will see them begin school at 10am.
- No topless scything when Poldark returns - acting and setting aside, the thing most people remember about the return of the Cornish drama to the BBC was Aidan Turner's Ross Poldark taking his top off. But this won't be happening in the next series, because it was filmed in the autumn and Cornwall was a bit chilly, writer Debbie Horsfield tells the Daily Telegraph. Better put a vest on, my lover.
- Captain Calamity: I'm in dock for good - also currently in Cornwall is 71-year-old American Steve Shapiro, or Captain Calamity to the Daily Mirror, so called because he's had to be rescued nine times while attempting to sail from Norway to North America. His 40ft boat has been moored in Hale harbour since January "where it tipped over and caught fire because his crewmate Bob Weise, also 70, failed to tie it up properly", reports the paper. He's now sold the yacht "after pleas from rescuers and sailing experts to hang up his captain's hat", the Mirror says.
'Difficult line to defend'
As the long-running dispute between junior doctors in England the government rumbles on, the Daily Telegraph reports on leaked emails from the head of the British Medical Association's (BMA) junior doctor's committee - uncovered by the Health Service Journal - in which he says a full walkout would be "difficult to defend".
Dr Johann Malawana's concerns are picked up in several other papers, including the Guardian, which reports the emails show he believed junior hospital doctors should continue to work in paediatric units during the strike, "because it is the right thing to do".
The Daily Mail says a second email from Dr Malawana said: "The reasoning being that doctors withdrawing care from children would be a difficult line to defend."
The Sun says Dr Malawana's plea "was rejected by hard-line committee members" and that the first full action in NHS history later this month means "junior medics will refuse to treat all cases, even if patients' lives are at risk". The BMA said doctors did not want to take action "but had no alternative", the paper says.
According to the Times four previous strikes by junior doctors have "failed to persuade the government to abandon plans to implement a controversial contract in the summer". The paper adds a quote from Health Minister Ben Gummer saying the BMA is "in turmoil" and that is "impacting directly on patient safety".
What the commentators say
The Daily Mail follows up on its front-page splash from Friday, in which the paper revealed that Mars Foods - the firm behind Dolmio pasta sauce and Uncle Ben's rice - was going to put labels on some products that they should only be eaten once a week because of their high salt, sugar or fat content.
Saturday's paper says other food firms "are refusing to follow" Mars' example, despite some of their food having similar quantities of the ingredients in question.
Celebrity chef Jamie Oliver is among those in the Mail's sights, as it reports that his tomato and basil sauce has more fat than a similar Dolmio product. But a spokesman for Mr Oliver ("famous for his campaigns to help get Britain eating healthily") tells the paper the products "fall within Department of Health guidelines for salt".
The Times reports that pressure is mounting on pasta sauce makers over labelling. Like the Mail, it has analysed the make-up of various pestos, pasta and lasagne sauces, and finds that some contain as much as 20% more fat and 5% more salt than the NHS guideline amount. One Lloyd Grossman sauce "contains the same amount of sugar as half a can of Coca-Cola", the paper says.
The Sun reports that campaigners have welcomed Mars' move, but unless other firms act "the government could make such labelling compulsory", it says.
The paper's also spoken to marketing expert Jacques de Cock, who says Mars have "found a clever way to to keep its popular foods unchanged whilst being seen to have families in mind and helping them make healthier choices".
'This service terminates here'
Several papers mark the death of Phil Sayer, best-known for being the voice of London Underground's "mind the gap" announcement, as well as the automated voice on platforms at some National Rail stations.
The Guardian reports that Mr Sayer's wife, Elinor Hamilton, posted news of his death on Facebook: "Phil Sayer - voice of reason, radio, and railways. A dearly loved husband, father, grandfather, brother, uncle and friend. We are sorry to announce that this service terminates here."
The Times says as well as urging Tube passengers to be mindful of the gap between the train and platform, Mr Sayer's voice could be heard "apologising for late running or explaining that the 7.32 would now depart from a platform on the other side of the station at 7.33".
The Daily Telegraph concurs, saying Mr Sayer's voice "became one that millions of commuters learnt to dread, as hearing it often meant that their trains had been delayed or cancelled".
The Sun reports how Mr Sayer considered being a voiceover was an exaggerated version of yourself and that "when you feel slightly ridiculous, you're probably doing it right".
"I do say sorry rather a lot," the Daily Mirror quotes him as saying. "But what can I say? I'm sorry but somebody has to do it!"
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