Conservative MP Nick Boles has quit the party after his efforts to find a solution to the Brexit deadlock were rejected by MPs.
Mr Boles said he was resigning the Tory whip “with immediate effect” because the party “has shown itself to be incapable of compromise”.
He said on Twitter that he would continue to sit in the House of Commons as an “Independent Progressive Conservative”.
Mr Boles, who served as a minister under former prime minister David Cameron, announced his decision in the Commons chamber after MPs failed to back any alternative options for Brexit in a second round of indicative votes on Monday.
In an emotional address to MPs 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.
“I accept I have failed. I have failed chiefly because my party refuses to compromise.
“I regret therefore to announce I can no longer sit for this party.”
His announcement was applauded by some MPs in the Commons chamber, while one could be heard saying: “Oh Nick, don’t go, come on.”
Mr Boles had twice tabled a proposal for a “Norway plus” plan for the UK’s future relationship with the EU.
This was defeated by 94 votes in the first round of indicative votes by MPs last week, and by 21 votes on Monday.
Mr Boles’ proposed scheme – known as Common Market 2.0 – would mean the UK joining the European Free Trade Association and European Economic Area.
This would have allowed continued participation in the single market and a “comprehensive customs arrangement” with the EU after Brexit.
In January Mr Boles joined Labour MP Yvette Cooper in tabling an ultimately defeated amendment to put Parliament in control of the EU withdrawal process.
Ahead of the first round of indicative votes in March, he warned that MPs could bring forward legislation forcing the Government to act if ministers try to ignore the wishes of Parliament.
Mr Boles has represented the Grantham and Stamford constituency in Lincolnshire since May 2010 and was re-elected at the June 2017 general election with a majority of 20,094.
In the Conservative-Liberal Democrat coalition he served as a planning minister for nearly two years.
He later worked as skills minister across the the Department for Business, Innovation and Skills and the Department for Education between July 2014 and July 2016.
Mr Boles, whose political interests include education, local government and foreign affairs, studied politics, philosophy and economics at Oxford University and public policy at Harvard.
Before entering politics he worked in helping state-owned industries prepare for private ownership and later set up his own paint brush and decorating tools business.
He was elected as a councillor in London in 1998 and a decade later was selected as the Tory candidate for his Lincolnshire seat.
Mr Boles also established and acted as director for the centre-right Policy Exchange think tank.