Tory MP Nick Boles dramatically quit the party as he slammed his former colleagues for refusing to compromise on Brexit options.
Mr Boles, who tabled a motion proposing a Norway-plus style Brexit, had previously quit his local party and resigned the whip following Monday's indicative votes.
Addressing the Commons, after his Commons Market 2.0 motion failed, he said: "I've failed chiefly because my party refuses to compromise.
"I regret therefore to announce that I can no longer sit for this party."
He then turned and left the benches.
A fellow MP could be heard saying: "Oh, Nick. Nick, don't go. Come on."
His motion, Motion D, had suggested the UK take membership of the European Free Trade Association and be part of the European Economic Area.
Mr Boles was previously the Conservative MP for Grantham and Stamford.
On his vote losing, he said: "I have given everything to an attempt to find a compromise that can take this country out of the European Union while maintaining our economic strength and our political cohesion."
Taking to Twitter shortly after he walked away from his party, he wrote: "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."
MPs rejected all options on the UK’s future relationship with the EU in a series of indicative votes for the second time.
Four alternative plans which were designed to establish what kind of Brexit has a chance of winning a majority in the House of Commons were voted on by MPs on Monday evening.
