Corbyn says Labour will back remain against no deal as McDonnell hints he may do so whatever the second option

Jeremy Corbyn has left the door open to staying neutral in a second referendum if the choice were between a Labour Brexit deal and staying in the EU, after his shadow chancellor, John McDonnell suggested he would campaign to remain in any circumstances.

The Labour leader was clear that the party would campaign to remain against a no-deal Brexit, as he pledged to do everything possible to prevent crashing out on 31 October.

But when asked if the party would stay neutral given a choice between a deal negotiated by Labour and remaining in the EU, Corbyn did not say which side the party would support.

“In a general election, we will put forward the opportunity for people in this country to have the final say,” he said on Monday. “It is not a rerun of 2016. It is simply saying the people of this country should make the final decision.

“If it is no deal versus remain then obviously John McDonnell and others made it very clear we would support remain. If there is the opportunity for some other option to be put then that will be put. I want to bring people together.”

He continued: “All I have been trying to do ever since the referendum is say there has to be an understanding of why communities around the country voted to leave because they see no investment, jobs or improvement in their livelihoods for a very long time and they are very, very angry. What we are offering is to transform our society and our economy.”

Asked whether he would personally campaign to remain in those circumstances, he said: “We have been very clear that in accordance with the democratic decision taken by our conference last year, an incoming Labour government will facilitate a choice where everyone will have a choice between a deal or remaining in the European Union.”

The precedents for neutrality would be the 1975 referendum, when the then Labour prime minister, Harold Wilson, allowed his cabinet to campaign on either side for and against membership of the European Community, while David Cameron also made the same decision for the Conservative party to stay neutral in the 2016 referendum on Britain’s membership of the EU.

Earlier, McDonnell appeared to take a different line when he made clear he would campaign to remain in the EU whatever the other option put forward in a second referendum.

He told BBC Radio 4’s Today programme: “I think generally people want to provide the electorate with a choice. I’ve made it clear from my personal position that I’ll be campaigning for remain. I think that’s the best choice.

“But people will want to have a say and see whether there is another option. But we’ve had that debate in parliament and that’s why I’ve come down in favour of remain because I can’t see one that will have the same benefits as remain.”

He was asked if he would be happy for the party as a whole to be “agnostic” on the issue, despite his personal wish to campaign to remain in the EU.

McDonnell replied: “That’s one of the issues we’ve got to debate in the party. You know our democratic processes. I know people get frustrated with this … but we’re a democratic party.”

The party’s policy could change at this year’s conference, where there will be a strong effort from pro-EU groups to shift Labour towards being an official remain party in all circumstances.

Corbyn set out his position in a speech in the key marginal Tory-held seat of Corby in the east Midlands, where he made the case that the UK’s problems run much deeper than Brexit.

Play Video 3:05 Corbyn speech sets out Labour's vision for Britain – video highlights

“A general election triggered by the Tory Brexit crisis will be a crossroads for our country. It will be a once-in-a-generation chance for a real change of direction, potentially on the scale of 1945. Things cannot go on as they were before,” he said.

“However the Brexit crisis is resolved, the country faces a fundamental choice. Labour offers the real change of direction the country needs: a radical programme to rebuild and transform communities and public services, invest in the green jobs and high-tech industries of the future, and take action to tackle inequality and climate crisis.”

The Labour leader accused Boris Johnson of being a “fake populist and phoney outsider” in the mould of Donald Trump as he set out his election pitch to transform the country as radically as Labour did in 1945 with the creation of the welfare state.

He also said Labour would do everything possible to stop a no-deal Brexit and called on opposition MPs and rebel Tories to “get on board” with his plan to hold a no-confidence vote, then form a caretaker government to extend article 50 and hold a general election.

Asked whether he could support another caretaker leader if he could not gain cross-party support, he said it was a role for the opposition leader to take on.

Following the leak of documents warning of protests and food shortages in the event of a no-deal Brexit, he attacked Johnson for the Conservative party’s “failure on Brexit, and its lurch to the hard right, which has provoked the crisis our country faces this autumn”.

“Boris Johnson’s government wants to use no deal to create a tax haven for the super-rich on the shores of Europe and sign a sweetheart trade deal with Donald Trump: not so much a no-deal Brexit as a Trump-deal Brexit,” he said.