Jeremy Corbyn has said there should be a second referendum on a Brexit deal if MPs demand one.
The Labour leader, who has come under mounting pressure to back another poll, ruled out a rerun of the 2016 referendum.
But he said: “If Parliament comes to an agreement then it’s reasonable, if Parliament wishes it, there should be a public vote on it, but that is some way off.”
His comments to ITV News came after he said an election or referendum is now the “only way out” of the Brexit crisis.
The Labour leader has been under intense pressure to explicitly back a referendum on Brexit after the European elections saw his party suffer heavy losses.
Divisions within the party were further exposed by the decision to expel Alastair Campbell, one of the architects of New Labour, for voting Liberal Democrat in protest against Labour’s Brexit policy.
Labour has sought to appeal to both Leave voters in its northern seats and Remainers in London and other cities, but lost half its MEPs and took just a 14% vote share as support switched to the clear alternatives offered by the Brexit Party and pro-EU Lib Dems and Greens.
Mr Corbyn said the Tory leadership contest – and the prospect of a “no-deal zealot” becoming prime minister – means the issue has to go to the public.
But in a sign that he would be prepared to work with Tory moderates to prevent a no-deal Brexit, possibly by tabling a confidence motion to bring down the Government, Mr Corbyn said he would do “whatever is necessary”.
He said: “Labour will work with anyone across party boundaries and do whatever is necessary to stop a disastrous no-deal outcome, which would open the way for a frenzy of deregulation and a race to the bottom in jobs, rights and protections.
“But faced with the threat of no deal and a prime minister with no mandate, the only way out of the Brexit crisis ripping our country apart is now to go back to the people.
“Let the people decide the country’s future, either in a general election or through a public vote on any deal agreed by Parliament.
“For Labour any outcome has to work for our whole country, not just one side of this deliberately inflamed divide.”