A petition to prevent US President Donald Trump coming to Britain on a state visit has been signed hundreds of thousands of times in a matter of hours.

The Republican's potential trip to the UK was already in jeopardy due to an expected row with the Prince of Wales over climate change, but Trump's so-called "Muslim ban" on travel has sparked a new row.

At the time of publication (6pm GMT, 29 January), the amount of signatures had nearly reached 500,000. It is expected to go beyond a million before midnight.

Regardless of the final figure, it has already reached the 100,000-signature threshold required for the matter to be debated at Parliament.

Graham Guest, a 42-year-old solicitor from Leeds, told IBTimes UK he started the petition after Trump's election and it had remained quiet until outrage about the executive order began.

He said: "I set the petition up about two months ago, but I didn't think it would do anything.

"I did it at the time of the election because I anticipated he would be invited for a state visit so I put that there on the website, but obviously, the state visit was only announced a couple of days ago so that's what got people interested.

"I think the 'Muslim ban' got people quite angry as well. People are looking at a way of getting at Trump and that petition is a way of achieving that because I think people think, 'Well, if you're going to ban people on some pretty spurious grounds…' then they were trying to make him know what it feels like to be banned from coming to the UK.

"From there, it just took a life of its own."

As the petition's tally increased and numerous politicians and celebrities voiced their anger, Theresa May has reportedly directed Foreign Secretary Boris Johnson and Home Secretary Amber Rudd to contact their US counterparts about the ban.

Earlier, she faced various criticism for not condemning the ban strongly enough and not standing up for British values.