JEREMY Corbyn's authority was in tatters after two-thirds of his shadow cabinet quit in an open revolt against his leadership.
The Labour leader is likely to face a challenge for his position after losing 20 members from his top team and a raft of junior frontbenchers over the last 24 hours as months of frustration exploded into a full-blown rebellion.
Mr Corbyn, who has vowed to fight on, was jeered as he used a Commons appearance to hit out at the rebels "indulging" in manoeuvres against him.
The Labour leader was flanked by stony-faced deputy leader Tom Watson as he delivered the rebuke to his MPs in the Commons.
There was further humiliation for Mr Corbyn as Hilary Benn – who he sacked as shadow foreign secretary in the early hours of Sunday morning – was cheered as he stood to speak during the Commons session on the EU referendum.
Earlier, Mr Watson held crisis talks with the leader and warned him he was likely to face a challenge to his position after losing the support of the parliamentary party.
The revolt has seen two-thirds of the shadow cabinet quit or, in Mr Benn's case, be sacked, while the party's leader in the Lords Baroness Smith of Basildon and chief whip Lord Bassam are set to boycott meetings of the top team while Mr Corbyn remains in place.
The referendum decision to leave the European Union has acted as the trigger for action by senior MPs against Mr Corbyn.
Former home secretary Alan Johnson, who ran Labour's campaign for a Remain vote in the referendum, claimed that Mr Corbyn's office had undermined the effort.
Despite Mr Corbyn's insistence that he was firmly behind the Remain cause, he has a history of Euroscepticism and the party's MPs have publicly questioned his commitment on the issue.
In an email to colleagues as Parliament returned following the vote for Brexit, Mr Johnson said: "I was proud to work with some great people who tried their very best to get the result we all wanted. Nobody in the leadership had the right to undermine their efforts."
But a spokesman for Mr Corbyn said: "Jeremy is disappointed by Alan Johnson's remarks about the leader's office. They are unfounded and appear to be aimed at undermining the Labour leadership."
Eight members of the shadow cabinet quit on Monday, with Angela Eagle, who as shadow first secretary of state deputised for Mr Corbyn at Prime Minister's Questions, the most senior.
She said Mr Corbyn needed to think about whether he should stay as Labour leader.
An emotional Ms Eagle told reporters outside Parliament: "I've made it clear that I don't think it's working, and Jeremy needs to think about his position."
Her twin sister Maria also resigned as shadow culture secretary, while John Healey, Lisa Nandy, Owen Smith, Nia Griffith, Kate Green and Luciana Berger also quit the shadow cabinet – adding to the 12 frontbenchers Mr Corbyn lost on Sunday.
In a joint statement Ms Nandy and Mr Smith told Mr Corbyn a leadership contest was "inevitable" and called for Mr Watson to take temporary charge of the party as "caretaker leader".
Mr Corbyn responded by appointing loyal MPs to key positions in an effort to shore up his position but the rolling resignations from his frontbench team underlined the scale of the challenge he faces.
In one of the biggest moves, former shadow defence secretary Emily Thornberry will replace Mr Benn, who was sacked as shadow foreign secretary in the early hours of Sunday morning.
In a sign of the chaos within the Labour ranks, Ms Thornberry's successor Clive Lewis was unable to take part in defence questions in the Commons because he was on his way back from the Glastonbury Festival.
Diane Abbott replaces Heidi Alexander, who quit as shadow health secretary – the first of the 11 shadow cabinet ministers who resigned on Sunday
Mr Corbyn is set to face a largely symbolic no-confidence motion at the Parliamentary Labour Party with the prospect of a secret vote today.
With a leadership contest looking likely, Mr Corbyn's office made clear that he would run and insisted he would automatically be on the ballot, without requiring the nominations of MPs.
Mr Corbyn believes he retains the backing of the grassroots activists who swept him to victory in 2015 and he also received fresh indications of support from union chiefs.
