After the leak of diplomatic cables that were heavily critical of US President Donald Trump, Britain's ambassador in Washington, Kim Darroch, has resigned. Trump had said his White House would no longer work with the envoy.

Darroch on Wednesday said he was resigning after his criticism of Donald Trump's White House drew the ire of the US president on Twitter.

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The envoy said that, although his posting was due to end later this year, he believed it would be better to leave early.

"The current situation is making it impossible for me to carry out my role as I would like," Darroch wrote in his resignation letter. "I believe in the current circumstances the responsible course is to allow the appointment of a new ambassador."

Trump slams Darroch

In the cables, Darroch had described Trump as "radiating insecurity" and described his administration as "clumsy and inept."

US President Donald Trump lashed out against Darroch in a series of tweets, branding the envoy "wacky” and "very stupid," and said he would no longer deal with the diplomat.

In the same Twitter barrage, Trump also branded UK Prime Minister Theresa May "foolish" for not following his advice on Brexit negotiations. On his state visit to the UK in June, Trump confirmed he told May how to leave the European Union, but admitted he did not know if the strategy would have worked.

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Darroch's future as the UK's ambassador came up as one of the issues in a bad-tempered television debate between the two rival candidates to succeed May as Conservative party leader and UK prime minister later this month.

Support from May

Outgoing British Prime Minister May has offered her full support to Darroch. May expressed "great regret" at Darroch's departure. "Good government depends on public servants being able to give full and frank advice," she said, emphasizing "the importance of defending our values."

May told parliament on Wednesday that British ambassadors should have the freedom to give frank assessments.

"I have told him it is a matter of great regret that he has felt it necessary to leave his position as ambassador to Washington," she said. "The whole cabinet rightly gave its full support to Sir Kim on Tuesday."

While May gave her full backing to Darroch, her potential replacement as prime minister, Boris Johnson, declined to explicitly support the diplomat and instead emphasized the need for maintaining good ties with Washington.

Darroch has received support from across the British political spectrum. Foreign Secretary Jeremy Hunt, who is also vying to replace May as leader of the ruling Conservative party, said "it should never have come to this."

On Tuesday, Hunt condemned Trump's outbursts as "disrespectful and wrong."

Commenting during an emergency foreign affairs select committee hearing on the issue on Wednesday, Simon McDonald, head of Britain's diplomatic service, said it was unprecedented during his 37-year career for the head of a friendly state to refuse to work with a British ambassador.

McDonald told the House of Commons that the last time the US had a problem with a British envoy was in 1856.

shs, rc/jm (Reuters, AP, dpa, AFP)

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