Jeremy Corbyn has resisted pressure for Labour to clarify its complex Brexit stance, despite calls from Europhile MPs and members to back remaining in the EU in all circumstances.
On Wednesday, the Labour leader repeated his promise last month to support a referendum on any Brexit deal, even one struck by a possible Corbyn government.
But he has declined to make an unambiguous commitment for Labour to campaign to stay in the EU, despite a public demand this week by Tom Watson, his deputy, for the party to come off the fence on the issue.
On Wednesday Mr Corbyn told the shadow cabinet: “I have already made the case . . . that it is now right to demand that any deal is put to a public vote.” He added that he wanted to carry out a further consultation with trade unions.
In one indication he is war-gaming a Remain position, he suggested that he could copy the approach of Harold Wilson, the Labour prime minister during a 1975 EU referendum, and allow senior Labour figures to campaign for either side.
One shadow cabinet attendee said Mr Corbyn gave the sense he wanted to resolve the issue before party conference in September.
A spokesman insisted that the party’s priority remained forcing a general election.
Labour and the shadow cabinet are still deeply divided by Brexit. The party’s 500,000 members are strongly pro-Remain, but the majority of its target marginal seats backed Leave.
Mr Corbyn has been urged for months by activists and MPs — including shadow Brexit secretary Keir Starmer — to reject Brexit altogether amid fears that pro-EU voters are switching to the Lib Dems and Green Party.
“We look indecisive, we look like we’ve been triangulating, we need to make our position clear,” said John McDonnell, shadow chancellor and a Corbyn ally who has gradually aligned himself with pro-EU forces in the party.
Later the shadow chancellor told a meeting of the Labour Business Group: “If we secure a referendum I will campaign for Remain and that is what I will be urging the party to do.”
Mr Corbyn made his commitment to a referendum on any deal — rather than just a Tory Brexit — hours after Labour was pummelled in last month’s European elections, when it picked up just 14 per cent of the vote.
But while 100 Labour MPs want a second referendum, more than 25 MPs wrote to Mr Corbyn on Wednesday urging him not to go “full Remain” and warning that another such vote would be “toxic”.
“There are at least 10 members of the shadow cabinet who do not want Labour to become the Remain party,” added one senior party figure.
Mr Corbyn himself, a long time Eurosceptic, is worried about alienating the 3m Labour voters who backed Leave in the 2016 EU referendum.
A presentation by Andrew Fisher, his policy chief, which was circulated at Wednesday’s shadow cabinet meeting, said it was “not obvious” that a more “pro-Remain” Labour position would win back enough voters from the Liberal Democrats to offset Leave voters in key marginals.
“There is an evident risk that shifting to a more explicitly pro-Remain position would leave us vulnerable in seats we need to hold or win,” it said.
Some of Mr Corbyn’s most senior advisers are also cautious about or opposed to a clear pro-Remain stance. These are Karie Murphy, his chief of staff, Seumas Milne, his head of communications, and Len McCluskey, head of Unite, Britain’s largest union.
“We have been arguing for a referendum with Remain on the ballot paper and Labour campaigning for reform,” said one member of the shadow cabinet. “But Karie, Seumas and Len are fighting a ferocious rearguard action over this.”
Perhaps the Labour leadership’s biggest dilemma is what position to take if there is a general election before Brexit takes place.
In those circumstances the party would either set out plans to negotiate its own exit deal with Brussels or campaign to revoke the Article 50 withdrawal process, cancelling Brexit entirely, according to insiders.
“You could make the case that enough time has passed for the original referendum result to have been overtaken by events,” said one Labour figure.
But a Corbyn ally said it would be “absurd” to adopt a position of Remain in all circumstances. It would be odd, for example, for a future Labour government to strike a new deal in Brussels and then urge the public to reject it.
Get alerts on when a new story is published