A Labour MP who campaigned for Britain to leave the EU is set to switch sides and vote Remain on 23 June, it has emerged.

Khalid Mahmood, the MP for Birmingham Perry Barr, will formally announce his change of heart tomorrow.

He said the Vote Leave campaign's focus on immigration was the main reason for the switch.

Mr Mahmood told the Telegraph: "The issue for me is the economy, but the debate has been hijacked by people to do with immigration and racism.

"When Boris Johnson talks about where Obama's father comes from, what's that got to do with anyone? Why do we need to talk about who his parents are? That disappointed a lot of people.

"Then there was the advert about passports and the campaign saying Turkey could join the EU - that 76 million people are coming to the UK and there have been a number of other things they used in a fairly racist context. I find that fairly offensive. My motivation originally was looking at the economy and the Commonwealth."

Mr Mahmood first announced in February that he was no longer backing the Labour Leave campaign, but stopped short of saying he would vote Remain.

His announcement comes on the same day that Tory MP Sarah Wollaston announced she was also switching from Leave to Remain.

The qualified GP said it was in protest at Vote Leave's claim quitting the EU would free up £350m a week to spend on the NHS.

"I could not have set foot on a battle bus that has at the heart of its campaign a figure that I know to be untrue," she told the BBC.

"If you're in a position where you can't hand out a Vote Leave leaflet, you can't be campaigning for that organisation."