UK Counter-Terror Police Probe Leak of Ambassador's Trump Cables

British police on Friday said they had opened an investigation into a leak of confidential memos that led to the resignation of the British ambassador to Washington.

Kim Darroch quit on Wednesday after Donald Trump called him "stupid" and "wacky" following the publication of the confidential memos by a newspaper. In them, Darroch called Trump's administration inept.

London's Metropolitan Police said its counter-terrorism command, which takes national responsibility for investigating allegations of criminal breaches of the Official Secrets Act, was leading the investigation.

"Given the widely reported consequences of that leak I am satisfied that there has been damage caused to UK international relations, and there would be clear public interest in bringing the person or people responsible to justice," Met Assistant Commissioner Neil Basu said in a statement.

"I would say to the person or people who did this, the impact of what you have done is obvious. However, you are now also responsible for diverting busy detectives from undertaking their core mission. You can stop this now. Turn yourself in at the earliest opportunity, explain yourself and face the consequences."

Basu added a warning to journalists and publishers that they could be in breach of the law if they published further details from the memos.

"The publication of leaked communications, knowing the damage they have caused or are likely to cause, may also be a criminal matter," he said.

"I would advise all owners, editors and publishers of social and mainstream media not to publish leaked government documents that may already be in their possession, or which may be offered to them, and to turn them over to the police or give them back to their rightful owner, Her Majesty’s Government."