Donald Trump's state visit to the UK is expected to be debated in Parliament after senior Conservatives joined more than 1.5 million people calling for it to be cancelled.

A petition calls for the visit, which is due to take place in the summer, to be abandoned because of the risk it will "embarrass" the Queen.

However, a Downing Street source has told the BBC that cancelling the trip would be "populist gesture" and "undo everything" achieved by Theresa May during her trip to the US last week.