Earlier today, deputy Labour leader Tom Watson warned the party could “cease to exist as an electoral force” if a secret plot to ensure the hard-left gained permanent control went ahead.
In an angry Twitter exchange with Jon Lansman, the founder of the pro-Corbyn organisation Momentum, he said: “You have revealed your plan. If you succeed you will destroy the Labour Party as an electoral force. So you have to be stopped.”
Lansman replied: “For 20 years the left was denied a voice. We will deny a voice to no-one. We face big challenges & we need our mass membership to win again.”
But it seems many Labour MPs share Mr Watson’s concerns, as a Parliamentary Labour Party (PLP) descended into chaos this evening.
The Labour leader was heckled by MPs – many of which were thought to be angry at the suggestion the party was too busy infighting rather than campaigning.
And others felt Mr Corbyn had failed to disclose any strategy on how to revive support, after an opinion poll showed Labour 19 points behind the Tories.
The poll comes just weeks after leaked data revealed Labour had lost almost 26,000 members since last summer.
Labour’s uselessness is emboldening the nationalist right wherever it exists
Following the Twitter spat this morning, Mr Watson was publicly backed by a number of Labour politicians as they too express their fears over the party’s future.
And many echoed the deputy leader’s concerns that Momentum appeared to be plotting a “secret deal” with Unite union boss Len McCluskey.
But Mr Corbyn sat in stony silence throughout the meeting tonight, sandwiched between Mr Watson and Scottish Labour leader Kezia Dugdale.
One MP said he looked “very uncomfortable” stuck between the pair, and the embattled leader cut a lonely figure as he slipped out alone after the meeting.
But while he faced his colleagues in silence, sources claim he was the only one not speaking out.
Moderate backbencher Ian Austin referred to “our so called leader” as he demanded to know why Mr Corbyn was not answering questions, with PLP chairman John Cryer responding in his place.
And one MP branded Mr Corbyn’s silence “unbelievable” as another left the rooming, exhaling: “F***’s sake.”
After the meeting, Peter Mandelson told reporters the atmosphere in the party now was like that in 1985, when the Militant Tendency attempted to take over.
But Lord Neil Kinnock, who as leader from 1983 to 1992 fought bruising battles against the hard-left group, told journalists: “No, it’s worse than that.”
Raised voices from inside committee room 14 in the Commons were so loud they could be heard clearly outside the room.
Shadow foreign secretary Emily Thornberry, a close Corbyn ally, was distinctly heard shouting at critic Wes Streeting, after he said the party was being “driven off a cliff”.
While Ex-minister Pat McFadden told the Labour leader: “Our uselessness is emboldening the nationalist right wherever it exists.”
And the former PLP chiarman Lord Watts savaged Mr Corbyn’s spin doctor Seamus Milne as “a disgrace”.
The comments come following a stormy meeting of the shadow cabinet earlier on Monday, after which Mr Corbyn and Mr Watson issued a joint statement agreeing to strengthen party unity.