Washington: Donald Trump's advisers fear he may not be able to stop himself intervening in the UK election when he visits London for a Nato summit on Wednesday, despite a plea from Boris Johnson.

The US President has been informed that Johnson does not want him to offer his support publicly, amid fears an endorsement could end up harming the Prime Minister's chances, and improving those of Jeremy Corbyn.

The Prime Minister and the President met at the UN in September. Credit:AP

But an insider says Trump may ignore the advice on the spur of the moment because he finds it hard to understand why his support would not be welcome.

"He's got the advice – but he doesn't have to take it. He gets to do his own thinking," a person close to the President said.