Almost 30 local parties are demanding Labour “support revoking Article 50 if necessary to prevent no deal”, in motions being submitted to its conference in September.
The move threatens to shatter the fragile peace over Brexit policy since the shadow cabinet agreed Labour would campaign for Remain in any fresh referendum held while the Conservatives are in power.
The policy was attacked as a fudge – after Mr Corbyn admitted Labour could yet fight a general election as a pro-Brexit party – and says nothing about wider strategy to stop the no deal Boris Johnson is threatening.
Meanwhile, the issue of withdrawing the Article 50 notice that started the withdrawal process could yet take centre stage in the parliamentary fight to stop no deal in autumn.
A cross-party attempt to pass legislation to force Mr Johnson to seek an extension of Article 50 is highly likely, but many MPs opposed to no deal believe any effort must go further to thwart the PM.
They fear Mr Johnson could simply refuse to cooperate with EU leaders – keeping a 31 October crash-out as the legal default – and want that default changed to require Article 50 to be revoked if no extension has been granted.
Now the local Labour parties have signed up to a campaign to maximise pressure in Brighton in September, launched by the grassroots groups Another Europe is Possible, Labour for a Socialist Europe and Open Labour.
The motion “notes the vast majority of Labour members and voters oppose Brexit” and says the party still needs “a clear Brexit policy”.
It then states: “Labour will campaign energetically for a public vote and to Remain. We support revoking Article 50 if necessary to prevent no deal.”
Lloyd Russell-Moyle, a Labour MP backing the campaign, said: “No deal would be a catastrophic moment for the Labour Party and the people we represent. It would mean a huge economic crisis which the right wing of the Tory party would use to drive an agenda of deregulation.
“We must be willing to do absolutely anything to stop it – and of course that would mean, if we had to, whipping to revoke Article 50.”
And Michael Chessum, national organiser for Another Europe is Possible, said: “It’s not the tool we would choose, but if revoking is the only option left on the table to stop the disaster capitalists, Labour has to be willing to use it. There can’t be any fudge or ambiguity on that.”
An online petition calling on the government to revoke Article 50 was signed by more than 6 million people earlier this year, making it the most popular petition ever submitted to the parliament’s website.
Last month he suggested Labour would fight the next election seeking to negotiate a better Brexit deal – if the UK is still an EU member – and said: “We’ll decide our policy when the election comes.”
The motions set the scene for a repeat of last year’s bitter tussle about Brexit policy, waged over a five-hour meeting to hammer out a compromise “composite” motion.
This year, anti-Brexit activists are likely to make a commitment to revoking Article 50, if necessary, a “red line” in the marathon Sunday evening get-together of constituency parties, trade unions and affiliated groups.
The conference will be staged just a month before the 31 October deadline for leaving the EU – with no sign of a new agreement with Brussels to avert a crash-out departure and the widespread damage predicted.
The activists also fear that if a snap election is called then conference could be cancelled, leaving Labour’s policy to be decided by a joint meeting of the shadow cabinet and the national executive committee.
They are urging the near-200 local parties to submit a motion to join the campaign to “shift the party’s position regardless of whether a formal conference vote takes place”.
In total, 50 constituencies have already voted to submit anti-Brexit motions to the Brighton conference, of which at least 29 explicitly call for the Article 50 notice to be withdrawn.
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