Britain's main opposition Labour Party begins its annual conference on Sunday desperately searching for a coherent Brexit plan to stem a potential drubbing in a looming election.
Labour leader Jeremy Corbyn's moment of truth comes with the crisis-torn country hurtling toward an October 31 exit from the European Union without a plan for future trade.
Yet the same divisions over Europe that saw Boris Johnson's right-wing Conservatives lose their working majority are also tearing apart Labour on the left.
The 119-year-old party's support base consists of cosmopolitan city-dwelling europhiles and traditional working-class communities that rejected Brussels in the 2016 referendum.
Polls show these views have become even more entrenched today - a polarisation that further complicates Corbyn's bid to find a unifying stance.
The strongly anti-European Brexit Party and the pro-EU Liberal Democrats are eroding Labour's support on both flanks, according to recent polls.
Labour officials will hunker down in a swanky hotel on England's south coast on Sunday night to whittle down their Brexit options to a single position that will be either rejected or approved on Monday.
Corbyn has given every indication that he wants Labour to stay neutral on the defining issue of UK politics.
"No, I am not sitting on the fence," he insisted in a testy ITV interview on Friday.
He has promised to negotiate a new divorce deal that maintains closer EU relations and then hold another referendum in which remaining in the bloc is the other option.
But he would not say which of the two he would campaign for - or whether he actually wants to stay or go.
"The British people will make that final decision," Corbyn told ITV.
Efforts to keep the peace by appeasing both wings of his party are not sitting well with voters ahead of an early election that most expect to happen within months.
A September YouGov survey showed that just half of self-identifying Labour supporters trust Corbyn's ability to "make the right decisions on Brexit".
The same poll said that fewer than 10% believed the 2016 Brexit decision was "right".
And an Ipsos MORI analysis found Corbyn's net satisfaction rating at -60. No opposition leader has fared worse in more than 40 years.
"This strategy of being all things to all people on Brexit - it paid off partly in 2017 (elections), but it's not clear that it's going to pay off again," said London School of Economics analyst Sara Hobolt.
"I think it wouldn't be right for Labour to have no opinion on such a big decision," Labour's foreign affairs spokesperson Emily Thornberry agreed.
"Labour should campaign for remain," she told The Guardian.
The push for Labour to reject Brexit is being resisted by a eurosceptic core of socialist Corbyn supporters who include his closest aides.
The rise of the veteran leftist followed a 2015 change in Labour leadership election rules that gave equal weight to the votes of both rank-and-file members and MPs.
Corbyn's left-wing views resonated with members and young people disillusioned by the New Labour approach of Tony Blair's more centrist government.
Tens of thousands joined the party and transformed its platform.
A group called Momentum that helped Corbyn become leader that year unsuccessfully tried on Saturday to abolish the post of the party's pro-European deputy leader Tom Watson.
Corbyn intervened and the second vote scheduled for Sunday was called off.
But Momentum boss Jon Lansman said it was time to instill party discipline and for everyone to adopt Corbyn's neutrality on Europe.
"We need to make sure the deputy leader role is properly accountable to the membership," he said.