Media playback is unsupported on your device Media caption Sarah Wollaston explains why she now supports the government view on the European Union.

Tory MP Sarah Wollaston has quit the campaign to leave the EU and will vote for Remain instead, she told the BBC.

Dr Wollaston, chairman of the health select committee, said Vote Leave's claim that Brexit would free up £350m a week for the NHS "simply isn't true".

She told the BBC she did not feel comfortable being part of the campaign.

Leave campaigners defend the £350m figure, saying it is the UK's gross contribution and any money received back is at EU officials' discretion.

But the Totnes MP, a former GP, said: "For someone like me who has long campaigned for open and honest data in public life 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.

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

'Unfortunate attacks'

Dr Wollaston said she thought there would be a "Brexit penalty" on the NHS because leaving the EU would hit Britain's economy.

301 Moved Permanently Moved Permanently The document has moved here. EU referendum issues guide: Explore the arguments http://www.bbc.co.uk/news/uk-politics-eu-referendum-36027205 https://www.bbc.co.uk/news/special/2016/newsspec_13606/content/iframe/english/index.inc.app.html Explore all the issues Choose an issue: What both sides are saying All issues Main views Share this page EU referendum issues guide What the leave and remain sides are saying in the #EUref campaign

"The consensus now is there would be a huge economic shock if we voted to leave," she said. "Undoubtedly, the thing that's most going to influence the financial health of the NHS is the background economy. So I think there would be a Brexit penalty."

Dr Wollaston defended her decision to change camps saying "nobody wants politicians who make the wrong decision" and it would be "far worse" not to change her mind.

Dr Wollaston said attacks Conservatives had made on each other during the campaign were "really unfortunate", and in a blog post, said the Leave campaign's focus on immigration made it look "increasingly indistinguishable from UKIP".

In February, Dr Wollaston accused Prime Minster David Cameron of "taking voters for fools" for suggesting refugee camps like the "Jungle" in Calais could move to England if the UK left the EU.

Media playback is unsupported on your device Media caption Vote Leave campaigner Priti Patel has said Tory MP Sarah Wollaston, who has quit the campaign to leave the EU, is "entitled to make up her own mind"

Mr Cameron tweeted that her decision to swap sides in the referendum debate was a "powerful intervention".

Vote Leave has been urged to stop using the £350m claim by the UK statistics watchdog and the Treasury select committee but the campaign insists that although Britain gets some of the money back it does not have control over how it is spent.

Cancellation of VAT on fuel

Speaking on BBC Radio 4's Today programme, Leave-backing Conservative John Redwood said he hoped Dr Wollaston would reconsider, but acknowledged the £350 million was the gross figure of the UK's contribution to the EU, before the rebate and the money that came back to the UK.

The former cabinet minister said: "Our Brexit budget has always concentrated on all the money we do send to them that we don't get back, which is about half of that gross total."

He added: "I hope Sarah will think again because she, like me, thinks we need to spend more money on health.

"We can do so out of all the money that we save and we would also be able to give that cancellation of VAT on fuel to people's households."

Leave campaigner Michael Gove has urged the government to commit to spend an extra £100m a week on the NHS by 2020 if Britain votes to quit the EU on 23 June.

Image copyright BBC News Image caption Sir John Nott was at Margaret Thatcher's side during the Falklands War

Meanwhile, in a blow to the Remain campaign, Sir John Nott, Conservative defence minister during the 1982 Falklands War, has suspended his membership of the party because of David Cameron's "tirade of fear" during the EU referendum campaign, according to The Daily Telegraph.

Sir John, who famously stormed out of a live interview with the BBC's Sir Robin Day during the Falklands War, is reported to believe that Mr Cameron and Chancellor George Osborne have "poisoned the debate" with their "frenetic" warnings about the consequences of a Brexit.