EXCL Labour set for conference clash over party's general election Brexit stance
Trade unions and Labour members are set for a major clash at the party's annual conference over Brexit, PoliticsHome understands.
The five-day event in Brighton will see the party thrash out its position on the UK's departure from the EU ahead of the looming general election.
Labour has committed to holding a referendum on any Brexit deal agreed by the Commons, with the option of staying in the bloc on the ballot paper.
But the party has not said whether its election manifesto will contain a pledge to campaign for Remain in all circumstances.
A majority of Labour members, as well as many of the party's MPs, believe it should take a stronger pro-EU stance.
The issue dominated a meeting of trade union bosses, John McDonnell, Jeremy Corbyn and senior Labour aides at the TUC's annual conference.
It is understood that Unite general secretary Len McCluskey made it clear to the Labour leader that the party must not commit to backing Remain if it wins the election.
One source said: "Len dominated the whole thing, with nobody else putting up any real fight.
"He said we should be clear that we will negotiate a Labour version of Brexit and there will be no attempt to advocate Remain in the referendum.
"Len's argument to Jeremy was that if he told the members this is the position we must take, they will support it out of loyalty to him. He believes that if that's the line Jeremy takes at conference, the members will fall into line."
PoliticsHome also understands that Mr McCluskey personally criticised Mr McDonnell, who has said he would vote Remain in any future referendum, and also told Mr Corbyn to crack down on other Shadow Cabinet members who break with the party's official position.
"He said 'you've got to make the Shadow Cabinet fall into line because they are sending out the wrong messages," the source said.
The deadline for Labour branches to submit motions for debate at conference passed this week, with a large number demanding that the party commit to overturning the result of the 2016 referendum - as the Lib Dems have done.
One senior trade union source told PoliticsHome: "It all points to the Brexit position being thrashed out again at conference."