Jeremy Corbyn's beleaguered leadership is facing yet more pressure as polling indicated more than half the members of Britain's biggest trade union want him to quit.
Some 49% of people signed up to Unite want the Labour leader to go immediately while a further 10% believe he should resign before the next general election, according to a poll seen by the Guardian.
Among Labour voters, 61% said he is doing badly in the job, the YouGov Election Data survey found.
Overall, 35% said Mr Corbyn should stay at the helm in the face of overwhelming opposition from MPs, MEPs and politicians in Scotland.
The YouGov poll had a sample size of just 775 voters but will be seized on by opponents at proof that Mr Corbyn's support is not assured on the ground.
It was not commissioned by the union, which has 1.4 million members, and general secretary Len McCluskey was among the first to rally to Mr Corbyn's support as the attempted coup to oust him emerged.
Mr Corbyn is expected to face a leadership challenge in "the next few days", according to his ally John McDonnell.
The shadow chancellor appealed to the party's MPs to "calm down" and settle Labour's differences through a democratic process.
Mr Corbyn is "staying as the leader of the Labour Party" and if there was a contest he could win, he insisted.
Deputy Labour leader Tom Watson is continuing to seek a meeting with Mr Corbyn's team to find a way of negotiating a settlement as the crisis engulfing the party shows no sign of abating.
Former shadow business secretary Angela Eagle is expected to mount a challenge to Mr Corbyn early next week, with ex-shadow work and pensions secretary Owen Smith also reported to be considering a bid.
In the last week around 60,000 people have joined Labour with the prospect of taking part in a leadership election.
But as both factions in the party have used social media campaigns to encourage supporters to sign up, it is not clear whether the boost in membership would benefit Mr Corbyn, who was swept into the leader's office on the back of a grassroots movement last year.
Scores of frontbenchers have quit in recent days, leaving Mr Corbyn with a seemingly impossible task in filling the vacancies after 172 of his MPs backed a no confidence motion in his leadership.
He was forced to appoint an English MP, David Anderson, as shadow Scottish secretary, a move that was branded "farcical" by the SNP.
A Unite spokesman said: "Unite's policy is made in 3,500 branches by at least 100,000 activists, by our policy conference and our elected executive council of lay members.
"This democratic procedure is not going to be set aside in favour of an opinion poll conducted by an organisation with a miserable accuracy record of late."