Theresa May was "very angry" about leaks of vital information about the Manchester Arena bombing to US media, Donald Trump has said.
Sensitive pictures from the Manchester Arena crime scene, including apparent images of a blood-stained detonator and rucksack, were leaked to US media - along with the identity of the bomber.
The leaks prompted fury from UK officials, and the sharing of intelligence was briefly suspended on Thursday before being reinstated following "fresh assurances".
On Sunday, the US president tweeted that Mrs May gave him "full details" of the incident during talks while he attended summits in Europe.
The Prime Minister said Mr Trump acknowledged the leaks were "unacceptable" when she challenged him about them.
Mr Trump said: "British Prime Minister May was very angry that the info the UK gave to US about Manchester was leaked. Gave me full details!"
Mrs May raised the issue with the US President at the Nato summit in Brussels on Thursday.
At a press conference at the G7 summit in Sicily on Friday, Mrs May said: "Yes, I did raise the issue of leaks of information that have been shared by the police with the FBI with President Trump. He has made clear that that was unacceptable."
Mr Trump's message was part of a series of tweets sent on his return to the US in which he hit out at leaks, "fabricated lies" and the "fake news media".