Mr Trump has previously claimed the streets of London and Paris are unsafe.

During his 2016 election campaign, he said that “London and other places… are so radicalised that the police are afraid for their own lives” as he defended his own plans for a “total and complete shutdown of Muslims entering the United States”.

Lord Cameron, who was then prime minister, said Mr Trump’s comments were “divisive, unhelpful and quite simply wrong”.

Boris Johnson, then serving as Mayor of London, said the comments were “ill-informed” and “utter nonsense”.

“The only reason I wouldn’t go to some parts of New York is the real risk of meeting Donald Trump,” he said.

Two years later, Mr Trump reportedly told Theresa May, then prime minister, that he thought there were “no-go areas” in London because of Islamic extremism. A source close to Mrs May said at the time that she had disagreed with that comment.

In 2018, after a car crashed into the gates of Parliament, Mr Trump tweeted: “Another terrorist attack in London…These animals are crazy and must be dealt with through toughness and strength!”

His comments came on the eve of the London mayoral elections in which crime has been a major campaign theme of both Labour’s Sadiq Khan and the Conservatives’ Susan Hall.

During Mr Trump’s state visit to London in 2018, Mr Khan gave protesters permission to fly a “blimp” of the Republican president depicted wearing a nappy and crying.

Mr Trump said during the visit that Mr Khan had “done a very bad job on terrorism”.