Police open inquiry into leak of dispatches sent by UK's ambassador to US Sir Kim Darroch
Scotland Yard has launched a criminal investigation into the leak of diplomatic dispatches sent by Britain's US ambassador Sir Kim Darroch.
The inquiry will be carried out by the Metropolitan Police counter terrorism command which is responsible for investigating breaches of the Official Secrets Act.
Assistant commissioner Neil Basu said: "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.
"The investigation will be reviewed at every stage to ensure a proportionate investigation is undertaken."
Sir Kim announced on Wednesday he was resigning, saying his position had become "impossible" following the leak of the cables in which he described Donald Trump's White House as "inept" and "dysfunctional".
His comments drew a furious response from the president who denounced him as a "very stupid guy" and a "pompous fool" and said the the White House would no longer deal with him.
The announcement came as Tory leadership front runner Boris Johnson admitted his reported lack of support for Sir Kim had been a factor in the envoy deciding to step down.
However he insisted his comments in a televised debate on Tuesday has been "misrepresented" and denied withholding his backing.
Mr Basu said the Met had been brought in following a cross-government investigation led by the Cabinet Office into the leak of the cables to The Mail on Sunday.
In a statement, he urged whoever was responsible to turn themselves in and face the consequences of their actions.
"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," he said.
"You can stop this now. Turn yourself in at the earliest opportunity, explain yourself and face the consequences."
Mr Basu also warned owners, editors and publishers of social and mainstream media not to publish leaked government documents, and to return any in their possession to their rightful owners.