Downing Street has rejected calls to postpone Donald Trump’s official visit to Britain after hundreds of thousands of people signed a petition calling for the trip to be cancelled.

A source has said that cancelling the trip would be ”populist gesture” and ”undo everything” achieved by Theresa May during her trip to the US last week. 

It comes after Boris Johnson secured assurances from the White House that the vast majority of British citizens will be exempted from Donald Trump’s immigration ban.

Last night the Foreign Secretary intervened with some of the American President’s closest advisers to ensure that UK citizens will be allowed to continue to travel from the UK to the US.

Mr Trump provoked a fierce backlash at the weekend after signing an executive order banning people from Iran, Iraq, Libya, Somalia, Sudan, Syria and Yemen from travelling to America.

Amid widespread confusion over who the new ban might apply to, concerns were voiced that British citizens who had been born in any of the seven countries would be barred.

Last night the Foreign Office confirmed that the ban will only apply to British dual nationality citizens flying directly from the countries identified as a risk to US security.