Keir Starmer received a prolonged standing ovation at the Labour Party conference on Tuesday after he said Brexit could still be stopped.
The shadow Brexit secretary told party activists that including the option to remain a member of the EU could be on the ballot in any second referendum.
He said if Theresa May could not be forced from office in a general election than there had to be “other options”.
“That must include campaigning for a public vote,” he told them.
“It is right that Parliament has the first say but if we need to break the impasse, our options must include campaigning for a public vote and nobody is ruling out Remain as an option.”
The commitment was seemingly ad-libbed on stage by Starmer, as it was not included in the released text of his speech.
He yesterday slapped down Shadow Chancellor John McDonnell for suggesting the public should not have the chance to vote for EU membership.
Delegates at the party’s conference are today expected to back a plan that could lead to a fresh referendum.
Party members will be asked to agree that “if we cannot get a general election, Labour must support all options remaining on the table, including campaigning for a public vote”.
Though some have described this as a “fudge” as it doesn’t go as far as committing the party to a second referendum.
The policy position came after hours of wrangling between different parts of the party over whether it should support another referendum.
Labour MP Alison McGovern, who supports the People’s Vote campaign for another referendum, said the standing ovation for Starmer showed “just how far” the party had come in a few weeks.
“The answer to this mess is a People’s Vote that gives voters the option of staying in the EU. That is what Labour members and supporters want and it is the direction in which Labour are now travelling,” she said.
Splits emerged at the top of the party yesterday after McDonnell suggested remaining in the EU should not be an option given to voters.
Instead he said the public should just be given the choice of what sort of Brexit deal they wanted.
Len McCluskey, the general secretary of the Unite union, has also said it would be “wrong” to re-open the issue of EU membership.
They were quickly contradicted by Starmer who said this was not what the party had agreed.
Starmer also confirmed today that Labour is highly likely to vote against Theresa May’s Brexit deal when it comes to parliament.
Labour’s position leaves the prime minister brutally exposed to a rebellion by restive Tory backbenchers, with fewer than a dozen able to fracture her fragile control of the Commons in the upcoming vote.
Brexit minister Robin Walker accused Labour of trying to take the UK “back to square one” and of wanting to re-run the referendum, saying: “Labour promised to respect the referendum result, but are just playing political games and trying to frustrate it.”