Boris Johnson as prime minister would mean the end of Corbyn’s Brexit fudge

Inside Westminster: Only a Remain alliance headed by Labour could defeat the combined forces of Johnson’s Tories and Farage’s Brexit Party in a general election

Corbyn needs to move with more speed than he is showing (PA)

Boris Johnson has got the contest he wanted against Jeremy Hunt, and is firmly on course for Downing Street. A Johnson premiership would cause shock waves way beyond his party. It would be the final nail in the coffin of Jeremy Corbyn’s Brexit policy.

Corbyn’s honourable attempt to unite the country by appealing to both Remainers and Leavers was also designed to unite his divided party. But “constructive ambiguity” has now become destructive for Labour. It is haemorrhaging support to pro-Remain parties, as last month’s European elections showed. Recent polls suggest only half of Labour’s 2017 supporters would back it in a general election.

Greg Cook, Labour’s long-serving polling expert, told the shadow cabinet that since March, the party has lost three votes (two to the Liberal Democrats and one to the Greens) for every one vote lost to Nigel Farage’s Brexit Party.

Doing nothing is no longer an option; Johnson’s arrival in No 10 could easily lead to an autumn general election in which he would seek a mandate for no deal.

In his report, Cook argued: “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 without enough potential seat gains in winnable Remain majority areas.” Corbyn’s close allies have used this argument to hold the line against giving unequivocal support to a referendum and Remain.

But it was challenged strongly at Wednesday’s shadow cabinet meeting by Tom Watson, Labour’s deputy leader. Later he told ITV’s Peston programme Labour “could be electoral history” if it did not make “a clear statement of intent” to back Remain.

Although a final decision was put off until next Tuesday, the shadow cabinet tide appears to be flowing Watson’s way. Those shifting in favour of a more pro-Remain stance include John McDonnell, Diane Abbott, Emily Thornberry, Sir Keir Starmer and Corbyn loyalists such as Richard Burgon, Dan Carden and Barry Gardiner.

Worryingly, Corbyn thinks he has already moved on a referendum since the European elections by backing one on “any deal” approved by parliament. He seemed surprised when a group of pro-EU Labour MPs he met this week did not know this. The episode highlights Labour’s problem: its message on Brexit has been deliberately fuzzy. If its own MPs don’t understand it, there is no hope the public will.

Corbyn should come out quickly and loudly for a Final Say referendum and pledge to back Remain in it. As a long-standing Eurosceptic, the most palatable message for him will be “Remain and reform” – change the EU for the better from within, rather than accept the status quo.

Lessons should be learned from Corbyn’s half-hearted effort in the 2016 referendum. “He wouldn’t have to lead the Remain campaign, but he must enable it,” one Labour frontbencher said.

PM Johnson would make a referendum more likely. Why? He is said to have been open to the idea in one-to-one meetings with pro-EU Tory MPs. Team Boris emphatically denies this; admitting it would infuriate hardline Brexiteers, who made Theresa May’s life a misery and could do the same to him.

More likely is the Commons imposing a referendum, with a helping hand from the speaker John Bercow. One senior Tory MP told me 50 of his colleagues would back a Final Say vote to prevent no-deal. For many, it would be preferable to the “nuclear option” of defeating their own government in a confidence vote and triggering an election.

Pro-EU MPs are convinced a “Remain alliance” – in a referendum or election – could succeed only if Labour heads it. Without that, Boris, aided by an electoral pact with Farage, could win a no-deal election, as the Lib Dems would struggle to turn their current poll rating of almost 20 per cent into seats under our archaic first-past-the-post system.

Corbyn told the shadow cabinet he has been reading a biography of Harold Wilson, the Labour prime minister who bridged the party’s Europe divide by allowing his ministers to campaign on either side in the 1975 referendum, which voted to remain in the then European Community. Like Corbyn, Wilson did not want to champion the European project. He stood back from the fray, just as Corbyn could do if Labour’s official position was crystal clear to the public. Corbyn could also copy Wilson’s “agreement to differ”, allowing Labour figures to campaign for Leave if they wished.

Corbyn needs to move with more speed than he is showing. There is a danger he leaves it too late. If he serves up more fudge, Labour’s annual conference in September will almost certainly impose a Remain position on him. It would then carry less conviction when it came from his lips.

There are other lessons from 1975. Sir Michael Palliser, the head of the Foreign Office, said Wilson’s conversion to the European cause was of the “head not the heart”. It would be the same for Corbyn, but that wouldn’t matter. A clear Labour Remain stance is now in the national and the party’s interest.