Boris Johnson refuses to criticise Donald Trump after he brands Theresa May "foolish" and her handling of Brexit a "mess."

"I can't dissent from that," Johnson told Politico when asked about Trump's comments.

The comments come after Johnson's colleagues accused the frontrunner to be prime minister of throwing the UK's ambassador to the US, Kim Darroch, "under the bus."

The opposition Labour party called him a "Donald Trump patsy."

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LONDON — Boris Johnson finds it "hard to disagree" with Donald Trump's attack on Theresa May, in which the president labeled her "foolish" and her handling of Brexit a "mess."

The frontrunner to replace May as Conservative party leader prime minister later this month, told Politico that he "can't dissent" from Trump's comments.

"I can't dissent from that," he said when asked about Trump's description of her deal as a "disaster."

He added: "When it comes to the context of what the president has said about the Brexit deal, I find it hard to disagree."

Pressed by Politico on whether it was right for Trump to personally criticise the prime minister, Johnson replied: "I think most people feel … I don't want anybody else telling us what to do.

"Or anybody else criticizing our government, I suppose is my feeling. But if you ask me whether I think the Brexit negotiations have been brilliantly handled, I don't think so."

The comments came after Johnson's colleagues accused him of throwing the United Kingdom's ambassador to the United States "under a bus".

Read more: Boris Johnson called a 'Donald Trump patsy' after throwing the UK's ambassador to US 'under a bus'

Johnson was branded "contemptible" by his colleagues and a "Donald Trump patsy" by his opponents, after reports suggested his refusal to back Sir Kim Darroch forced the UK's ambassador to the US to resign.

Darroch was forced out on Wednesday, saying that it was "impossible" for him to remain in post after a public row with the US President.

The UK's top diplomat in Washington resigned after confidential memos he wrote labeling Trump's administration "dysfunctional" and "incompetent" were leaked to the press over the weekend.