The suspected leaker of confidential cables from Britain's ambassador to the U.S. has been identified, the Sunday Times reports, as fresh leaks to the Mail on Sunday claim President Trump abandoned the Iran nuclear deal to "spite" predecessor Barack Obama.

Details: The latest leak shows Kim Darroch, who resigned Wednesday, expressed his thoughts on the Iran situation to then-Foreign Secretary Boris Johnson — the front-runner to replace Prime Minister Theresa May as Conservative Party leader. He wrote that Trump withdrew the U.S. from the 2015 agreement for "personality reasons" as it was the former president's pact.

"The outcome illustrated the paradox of this White House: you got exceptional access, seeing everyone short of the president; but on the substance, the administration is set upon an act of diplomatic vandalism, seemingly for ideological and personality reasons — it was Obama's deal.

"Moreover, they can't articulate any 'day-after' strategy; and contacts with State Department this morning suggest no sort of plan for reaching out to partners and allies, whether in Europe or the region."

— Leaked Kim Darroch memo

The big picture: British Police said Friday they had launched a criminal investigation into the source of the leaks. The Sunday Times quoted an unnamed British government source as saying that the suspected leaker had been identified and investigators had ruled out that the leak was the result of a computer hack by a foreign state.

The Sunday Times reported that Member of European Parliament Richard Tice, the chairman of Nigel Farage’s Brexit Party, was implicated in the leaks scandal as he's dating Isabel Oakeshott, the Mail on Sunday journalist who's been writing the Darroch articles.

What they’re saying: Metropolitan Police Assistant Commissioner Neil Basu's warned journalists not to report on leaked diplomatic memos — prompting criticisms from Johnson and his leadership rival, Foreign Secretary Jeremy Hunt, the BBC reports. Johnson said it's right for the leaker to be "hunted down and prosecuted," but it's wrong for police to target the media, according to the BBC.

This article has been updated with more details, including comment from Johnson and Hunt.

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