The Grantham and Stamford MP Nick Boles has resigned from the Conservatives blaming his party for failing to compromise over Brexit.
He said on Twitter: "I am resigning the Conservative whip with immediate effect. The Conservative Party has shown itself to be incapable of compromise so I will sit as an Independent Progressive Conservative."
Mr Boles, who has been the MP for the south Lincolnshire constituency since 2010, was the architect of Common Market 2.0 - one of the options MPs have been voting on to withdraw from the European Union.
It was rejected by 21 votes as MPs failed to reach a majority on any of the four alternatives to Theresa May's EU withdrawal deal after Parliament took control of the Brexit process for the second time in the space of a week.
A proposal from Europhile Tory grandee Kenneth Clarke for a customs union arrangement with the EU was rejected by only three votes, while a demand for a second referendum was defeated by 12.
The Brexit Secretary and North East Cambridgeshire MP Steve Barclay told MPs that the default outcome was now a no-deal Brexit on April 12.
Mr Barclay said it was still possible to leave with a deal - and avoid holding European Parliament elections in May - if the Commons approves an agreement this week.
Nick Boles quit the Conservative Party in a dramatic and emotional speech in the the House of Commons chamber after his Brexit alternative was defeated for a second time.
The former minister said he "could no longer sit for this party", prompting one colleague to say: "Oh Nick, don't go, come on."
He was applauded by other MPs for his announcement, which came moments after his Common Market 2.0 proposal was rejected again by MPs.
Mr Boles acknowledged he had "failed" but blamed this "chiefly because my party refuses to compromise".
His plan sought UK membership of the European Free Trade Association and European Economic Area and received cross party support, but lost by 282 votes to 261.
The Conservative MP for Rayleigh and Wickford in Essex Mark Francois said: "This evening, an attempted coup took place in the House of Commons, involving leading members of the Cabinet and backbenchers to prevent Brexit. The coup failed.
The vice-chairman of the European Research Group faction of the Tory Party added: "The simple fact is Tory backbenchers, having realised what was going on rallied and defeated all the non-Brexit options and as a result we're now on track to leave the EU in 11 days time, in accordance with the wishes of the 17.4 million."
The North East Bedfordshire MP Alistair Burt, who resigned as a government minister last week said the Prime Minister would not allow a no deal to take place.
He said: "The Prime Minister has made it very clear on a number of occasions she is very concerned about a no deal.
"She's said that for no deal to happen we would have to have express consent in the House of Commons.
"I hope we don't have a general election because I don't see what a general election would do to resolve the situation, it leaves the decisions that still have to be made until after the election."