Newspaper headlines: Trump 'axed Iran deal to spite Obama' and whistleblowers 'to sue Labour'
Warnings by police have not deterred the Mail on Sunday from publishing more leaked cables from Sir Kim Darroch.
The paper argues that it is "fighting for free speech".
To bolster its argument, it pictures the two contenders to be the next prime minister on its front page - both defending the right of the press to publish material in the public interest.
It says that she is in a relationship with Richard Tice - the MEP who is chairman of Nigel Farage's Brexit Party and it claims he has become embroiled in the leak scandal.
The article says police believe that a pro-Brexit civil servant took the Darroch material to try to undermine officials who do not support leaving the EU.
It also quotes an unnamed diplomat who suggests there are a lot of Brexit Party fingerprints on the disclosures. But the paper notes that both Ms Oakeshott and Mr Tice have denied that he played any role in the leak or the handling of the documents.
The former Conservative foreign secretary, Sir Malcolm Rifkind, writing in the Observer, launches an attack on Boris Johnson for his treatment of Sir Kim Darroch.
He says he can't think of a previous occasion where an ambassador has had to resign because he told the truth. He believes Mr Johnson's refusal to defend Sir Kim doesn't bode well if he becomes the next prime minister.
And there's nothing like a threat to press freedom to get the leader writers going.
The Mail on Sunday comment occupies a full page. It quotes Lord Northcliffe - the inventor of modern, popular newspapers, who said: "News is what somebody somewhere wants to suppress".
The Mail admits Sir Kim Darroch's emails "ignited a controversy in high politics" but questions the idea that the story resulted in "national damage".
The paper thinks it's absurd that a truthful and accurate leak of significant material, enabling voters to be better informed, should be met by threats of prosecution.
For The Sunday Times, the matter is simple - "We'll decide what to publish, not Scotland Yard".
"Chilling", "unprecedented" and "heavy-handed" is the Sunday Telegraph's assessment of the warning issued to the media.
The Sun on Sunday wonders whether Assistant Commissioner Basu has been holidaying in North Korea.
The former editor of the Guardian, Alan Rusbridger, calls for classes in free speech at police college.
But the Observer believes the Metropolitan Police performed a climb-down when the senior officer issued a second statement clarifying the force didn't want to stop the press from publishing stories.
Meanwhile, the same paper says that two of the whistle-blowers who featured in the BBC Panorama programme about allegations of anti-Semitism in Labour intend to sue the party for defamation.
They allege that in its response to the programme, Labour painted them as disaffected former officials who had falsely made deliberate, malicious representations. The party tells the paper that any legal action would be vigorously defended.
The Observer also reports that Labour - which has complained to the BBC that the programme was "slanted" - is trying to force the corporation to remove it from the iPlayer.
Some of the papers try to work out what a future Boris Johnson cabinet would look like. The Sunday People says that city insiders - who've been talking to Mr Johnson's team - believe the current Home Secretary, Sajid Javid, will become the next chancellor.
And it tips the former Defence Secretary, Sir Michael Fallon, or the Brexiteer, Iain Duncan Smith to replace Jeremy Hunt as Foreign Secretary.
The Mail on Sunday also thinks Mr Hunt will be demoted because his leadership campaign has infuriated Mr Johnson. And it claims the former Brexit Secretary, Dominic Raab, is being considered for No 11.
According to the Sunday Mirror road safety chiefs are considering new measures to stop what it calls "phone zombies" from being run over.
It says warning lights could be installed in pavements at crossings to catch their eye. It cites government research which shows that looking at phones and listening to music is a big factor in seven- to 16-year-olds being knocked down.
The Last Night of the Proms is regarded as one of Britain's most traditional festivals but The Sunday Times reports it plans to stage its own celebration of gay pride.
This will involve the American mezzo-soprano, Jamie Barton - who is bisexual - singing "Over the Rainbow" - which has become adopted as the gay movement's anthem.
She says she intends to wear a pink, lavender and blue concert gown - colours associated with bisexual activists. The paper believes the idea is "daring" for an event usually dominated by "nostalgic Britishness".
The Sunday Mirror leads with an interview with the widow of Lee Pomeroy, who was murdered after arguing with a stranger on a train to London.
Lana Pomeroy tells the paper she feels racked with guilt that she hadn't joined her husband on the fateful trip - believing things may have ended differently.
As the 50th anniversary of the moon landing nears, the Sunday Telegraph reports that President Kennedy had not intended the Apollo programme to be a nationalistic endeavour.
It covers research, by a former member of Nasa's advisory council, which says the former president had intended to join forces with the Soviet Union to put a man on the moon.
But its leader, Nikita Khrushchev, declined - setting up the bitter space race between the two countries.
There's plenty of coverage of what the Daily Express terms "Super Sunday". The paper says millions will tune in for an epic day of sport topped by the Cricket World Cup final.
The former cricket captain, Alastair Cook, offers his prediction for the match in The Sunday Times under the headline, "England Must Answer Lord's Prayers".
He says if the home nation play their best then they will win. But he warns of the danger posed by New Zealand's Trent Boult and Kane Williamson - a bowler and a batsman who, he says, would merit selection in any world eleven.
The Sunday Telegraph says England stand on the brink of glory - underlining the stakes with the headline, "Do or die!"