President Donald Trump decided to freeze out Kim Darroch, saying he would no longer deal with the man who had called his administration “inept” and “uniquely dysfunctional.”

In a statement released by the U.K. government, Darroch announced he would quit after a “difficult” few days. “The current situation is making it impossible for me to carry out my role as I would like,” Darroch said.

The resignation follows a sustained attack from Trump, who on Tuesday described Darroch as a “pompous fool.”

Johnson’s Move

Perhaps more difficult for Darroch was the response of Boris Johnson, the man who is likely to be the U.K.’s next prime minister. During a televised debate on Tuesday, Johnson declined to back Darroch and would not commit to keeping him in his job, in sharp contrast to the endorsements and support the ambassador received from other senior British politicians.

“Since the leak of official documents from this Embassy there has been a great deal of speculation surrounding my position and the duration of my remaining term as ambassador. I want to put an end to that speculation,” Darroch said. “Although my posting is not due to end until the end of this year, I believe in the current circumstances the responsible course is to allow the appointment of a new ambassador.”

A spokesman for the U.K. Foreign Office said Darroch would stay on until a new ambassador takes over, although a caretaker envoy could be appointed to allow him to leave the Washington post sooner.

“I have told him that it is a matter of great regret that he has felt it necessary to leave his position as ambassador in Washington,” Prime Minister Theresa May told Parliament on Wednesday. “The whole Cabinet rightly gave its full support to Sir Kim.”

May said all officials need to be confident “to give full and frank advice” and urged MPs to “reflect on the importance of defending our values and principles, particularly when they are under pressure.” That sounded like a veiled criticism of both Trump, for his attacks, and Johnson — May’s long-term rival — for his refusal to back the diplomat.

Johnson’s opponent in the contest to succeed May, who stands down later this month, did give his wholehearted support to Darroch. Jeremy Hunt, the foreign secretary and Darroch’s direct boss at the Foreign Office, hit back at Trump on Tuesday, saying the president’s outburst had been “disrespectful and wrong.”

On Wednesday, Hunt said he was “deeply saddened” that Darroch is standing down. “I profoundly regret how this episode has led Sir Kim to decide to resign,” he said in a statement.

For Johnson, there is a risk that Darroch’s departure could rebound on him. Wednesday’s newspapers contained headlines accusing Johnson of betraying his country by failing to support the diplomat.

‘Under a Bus’

Alan Duncan, a minister in the Foreign Office, said Johnson had thrown Darroch “under a bus” by refusing to back him during Tuesday’s TV debate. “The respect held for Boris Johnson has taken a serious nose-dive today,” Duncan told the BBC.

On a campaign visit to a pub in London, Johnson tried to play down his role in the diplomat’s resignation. “My view is it’s wrong to drag civil servants into the political arena,” he said.

Darroch has worked for the Foreign Office since 1976, holding diplomatic posts all around the world. He acted as national security adviser before taking on the role as U.K. ambassador to the U.S. in 2016.

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