Boris Johnson has expelled 21 MPs from the parliamentary Conservative Party after they rebelled against him in a bid to prevent a no-deal Brexit.
Those who have had the Tory whip removed include two ex-chancellors and a number of senior figures in Theresa May's and David Cameron's governments.
Some have said they will stand down at the next election - whilst others have vowed to fight attempts to stop them standing again as Conservative candidates.
It comes after the rebels teamed up with the opposition on Tuesday to back a motion paving the way for a law seeking to delay the UK's exit date.
The legislation would force the prime minister to delay Brexit until January 2020, unless MPs approve either a new deal or a no-deal exit by 19 October.
So who are the Tory MPs who rebelled against the prime minister?
The former chancellor, who has been co-ordinating the rebels' efforts, insisted the move was not simply designed to block a no-deal exit but also to give Parliament proper time to scrutinise and implement any new deal agreed.
The 63-year-old voted for Theresa May's Brexit agreement three times, but has become a bogey figure for many Tory Brexiteers. They believe he has consistently exaggerated the economic risks of Brexit and sought to frustrate planning for no deal while in charge of the Treasury.
The Runnymede and Weybridge MP has said he will vigorously contest any attempt to deselect him as a candidate in the next election, potentially through legal action.
But his constituency association, which officially re-adopted him as their candidate on Monday evening, issued a statement on Facebook stating that he would "no longer be eligible to stand" after losing the Tory whip.
"A new Conservative candidate will be selected by the membership in due course," it said.
Theresa May's former justice secretary is another key figure - so much so that he and his anti-no-deal associates have been dubbed the "Gaukeward squad".
The 48-year old former solicitor - who was George Osborne's number two at the Treasury in pre-referendum days - has said a no-deal exit would be a "big mistake" for the UK and he would not be "complicit" in something which would see people lose their jobs.
The South West Hertfordshire MP faced calls earlier this year from some activists in his constituency to deselect him.
Confronted with the same threat now from No 10, he said he was prepared to put the national interest ahead of his own future career prospects by voting against the government. He said he believed Downing Street wanted to carry out a "purge" of dissenting voices.
Unlike Mr Hammond and Mr Gauke, Mr Grieve has been a frequent and high-profile rebel over Brexit during the past two years - opposing Theresa May's withdrawal deal three times.
The former attorney general is a strong supporter of another referendum on the UK's future in Europe, with the option to remain.
The 63-year-old says he regards a no-deal exit as "unacceptable" and will always vote against it - even if his career takes a hit.
The Beaconsfield MP has said he wants to fight the next election as a Conservative but being deselected is a price he is willing to pay.
His constituency chairman, Jackson Ng, said he had urged Mr Grieve to "desist" from rebelling but thanked him for his "long service".
Earlier this year, Mr Grieve lost a vote of no confidence by local Conservatives following a "robust discussion" about Brexit.
Another former chancellor, Mr Clarke is the most strongly Europhile member of his party and has long been out of step with its views on Europe.
He opposed the 2016 Brexit referendum and was the only Tory MP to vote against triggering the Article 50 process for leaving the EU.
He has gone as far as to suggest he would vote against the government in a vote of no confidence in order to stop a no-deal exit.
The 79-year old has previously suggested he might stand down as MP for Rushcliffe at the next election.
His constituency association said it was saddened to lose him from the party and paid tribute to his "enviable and unparalleled" service since he was first elected in 1970.
It added that "all future correspondence should be sent direct to his office at the House of Commons rather than to the Rushcliffe Conservative Association office".
Sir Oliver Letwin
The ex-cabinet minister was a ringleader in attempts by MPs in April to hammer out a Brexit compromise by seizing control of the parliamentary timetable.
He also spearheaded a cross-party bill designed to compel Theresa May to seek a Brexit extension earlier this year, and was the MP who applied for an emergency debate on Tuesday, beginning the process which led Boris Johnson's defeat over the latest no-deal Brexit bill.
A consummate Westminster insider, he is a leading "soft Brexiteer" who believes the referendum result must be honoured but the UK should maintain close economic links with Europe.
The West Dorset MP had already said he will not contest the next general election.
The former education secretary announced on Tuesday she would stand down as MP for the overwhelmingly pro-Remain constituency of Putney in south-west London whenever the next election comes.
She warned that Parliament's ability to be a force for change, particularly in terms of improving social mobility, was being compromised by "Brexit myopia".
She voted three times against Theresa May's Brexit agreement, saying it neither delivered on the promises made to Leave voters nor gave anything to younger Remain.
Warning her party was morphing into The Brexit Party, she said she would support legislation to keep all Brexit options "on the table" and to ensure Parliament has a real say in the outcome.
The former international development secretary said claims a no-deal exit would be a "clean and easy break" from the EU were disingenuous as, in reality, it would lead to years of economic and political uncertainty.
Mr Stewart suggested such an outcome would be "remembered for 40 years", and would permanently damage the party's reputation.
Despite losing the whip, he has said he is "not giving up" on his Cumbrian constituency and would still be representing residents of Penrith and the Border.
He says it should be up to his local association whether to let him contest the next election and "purging" him and other rebels as candidates was a not a Conservative response.
The former Middle East minister, a respected figure in the party, has said he has a "fundamental and unresolvable" disagreement with the party leadership over Brexit.
He has said he will standing down as MP for North East Bedfordshire at the next election, having served in the Commons since 1983.
Speaking in the Commons, he said he accepted the party rules but asked colleagues to reflect on the question "if we are being purged now, then who is next?".
He said the Brexit convulsions in his party "may have curtailed my future but it will not rob me of what I believe, and I will walk out of here looking up at the sky, not down at my shoes".
Sir Nicholas Soames
Winston Churchill's grandson was among those who met the PM on Tuesday for last-ditch talks but rebelled after concluding a deal was not achievable in the available timeframe.
Speaking in the Commons, he joked that he had been "inspired by the serial disloyalty" of the prime minister and other members of the current cabinet over Brexit in the past.
He added that it was his "most fervent hope is that this House will rediscover the spirit of compromise, humility and understanding" required to bring Brexit to a resolution and refocus on all the other challenges facing the country.
Having had the whip removed, he has said he will not be standing at the next election - meaning his near 37 year Commons career is nearing its end.
Dame Caroline Spelman
The veteran Conservative MP for Meriden supported the government in Tuesday's vote on whether to seize control of Parliamentary business.
But she joined the ranks of the rebels when the bill paving the way for a further delay to Brexit, if no deal is achieved, was voted on for the first time.
Unlike those who rebelled on Tuesday, she has not had the whip withdrawn - but she has said she will not be standing at the next election.
A former Conservative party chair and environment secretary under David Cameron, her Midlands constituency is home to a number of firms supplying parts for the UK car industry.
The 61-year old has expressed concerns about the impact of a no-deal Brexit on the industry.
Other MPs who rebelled:
Greg Clark: The former business secretary was one of the strongest advocates of Theresa May's Brexit deal. He has said no deal would be "ruinous".
Sam Gyimah: The former universities minister said there was "no mandate" for a no-deal exit which would be "damaging and disruptive" for his constituents.
Antoinette Sandbach: The MP for Eddisbury said it was "important to act" to stop any chance of no deal. She said she did not "regret putting her job on the line to save my constituents' jobs".
Stephen Hammond: He has accused Tory Brexiteers of "lecturing others" about loyalty. He told the BBC's World at One he would "reluctantly" vote against the government.
Margot James: The former digital minister said it had been the hardest decision she had ever made in politics. Her local Stourbridge Conservative association has begun the process of selecting a candidate for the next election, saying the choice was a "matter for members".
Richard Harrington: The 61-year old has rebelled over Brexit before and recently announced he would stand down as MP for Watford at the next election.
Guto Bebb: The Aberconwy MP, who is also quitting at the next election, says a vote against no deal is "truer to Conservative tradition than anyone who traipses through the lobbies out of fear, opportunism or simply unthinking loyalty".
Caroline Nokes: The Romsey and Southampton North MP said her constituents would be worse off under a no-deal Brexit. She said she would be talking to her constituency association but would not rule out standing as an independent.
Ed Vaizey: The ex-culture minister has said a no-deal exit would hurt the digital economy although he told Buzzfeed News he had yet to decide which way to vote.
Steve Brine: The former health minister said last week he was prepared to hold the PM to his claim a no-deal exit is a "million to one chance".
Anne Milton: She has kept a low profile since quitting as a minister in July but attended a meeting with other likely rebels in Westminster earlier on Tuesday.
Richard Benyon: The MP for Newbury is a former fisheries minister in the coalition government. He told the BBC that he hoped to return to the fold as a Tory MP, adding that he would "throw himself on the mercy" of his local association.
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