Donald Trump’s leadership has been compared to the rise of the Nazis by the former British ambassador to the US.
Sir Peter Westmacott, who left Washington in January 2016, tweeted to say Trump’s presidency had “shades of 1933 Germany” - the year Hitler came to power.
He also said the president’s behaviour was “an invitation to autocrats without America’s checks and balances to play the same game more dangerously”.
Westmacott, who was succeeded by the current ambassador Sir Kim Darroch, made the remark in response to a tweet by NBC journalist Andrea Mitchell.
She quoted former Director of National Intelligence James Clapper, who has called Trump’s rhetoric “scary and disturbing” and questioned his fitness to be president.
Westmacott’s comments followed a frenzied Trump rally in Phoenix, Arizona, on Tuesday where he said more to condemn the media than white supremacists during a meandering, 77-minute speech.
It follows his equivocation over whether he categorically condemned white supremacists and neo-nazis for the violence at the deadly Far Right rally in Charlottesville, Virginia.
Westmacott has previously been critical of Trump’s White House.
In March, he said Trump was “gratuitously damaging” the UK-US relationship by “peddling falsehoods” after his then spokesman Sean Spicer suggested GCHQ had tapped Trump Tower at Barack Obama’s request.
The president had insisted, without evidence, his phone had been tapped.
Westmacott wrote in The Guardian: “Anyone with any knowledge of the intelligence world knew the suggestion was absurd.
“First, the president of the United States does not have the power to order the tapping of anyone’s phone.
“Second, the idea of the British foreign secretary signing a warrant authorising such an intrusion into domestic US politics was unthinkable.”