Party leader says concerns over workers’ rights and environment could force move and remains open to second referendum

Jeremy Corbyn has said Labour would be prepared to vote down Theresa May’s final Brexit deal this autumn in an attempt to force the government back to the negotiating table with Brussels because the party has been concerned about a dilution in workers’ rights and environmental standards.

The Labour leader also repeated that he was open to the idea of a second referendum if the party agreed to that policy later this week, although he added he would wait and see what wording would be put in front of the delegates after a meeting on Sunday evening.

In an interview with Andrew Marr, Corbyn said of May’s final Brexit deal: “We would vote it down if it didn’t meet out tests, in order to send the government – if it is still in office – straight back to the negotiating table.”

Corbyn says he will accept any Labour conference decision on second Brexit referendum - Politics live Read more

“We want to protect jobs and industry in the country,” he added.

In November the UK parliament is expected to vote on whether to approve whatever Brexit deal May brings back from her negotiations with the European Union.

Conservatives backing hard Brexit have already threatened to vote against the deal if May continues with her Chequers plan to keep the UK in the single market for food and goods, meaning that if Labour were to vote against it as well, its passage through the Commons would be far from certain.

A debate on a second referendum has been called for by over 100 constituencies, who have sent in motions asking the party to support it, following a debate on the conference floor. The motions will be consolidated on Sunday evening in a process known as compositing, which will determine the final wording of the resolutions to be put to a vote of delegates on Tuesday.

The exact wording chosen may end in a fudge, probably keeping a new poll on the table but stressing preference for a general election. A further leadership statement on Brexit could still be submitted on the day of the debate, which could trump the composite motion.

Q&A What is 'compositing' at the Labour conference? Show Hide In the run-up to the Labour conference, local parties can submit motions on any contemporary topic for debate. After a concerted push by grassroots activists, more than 150 constituency parties (CLPs) have submitted motions on Brexit, an unprecedented number. For comparison, the topic with the second highest number of motions submitted – the NHS – has been put forward by 10 CLPs. However, the motions are not identical. The majority call for a second referendum directly, some express preference for an election, others call for an EEA-style Brexit. When different motions are submitted on one topic, delegates from the local parties who submitted motions, as well as trade union representatives, meet the shadow cabinet member responsible, in this case Keir Starmer, to agree a "composite motion" to be put to the conference floor for a vote. This is usually a compromise taking in all the elements of the different motions. Usually this is a straightforward process, because there are only a handful of delegates and union reps in the room. This time, there are likely to be more than 100 people in the room from all the local parties who submitted motions, so things could get complicated. The final version is likely to be a compromise which expresses preference for an election but keeps the option of a referendum on the table. And Labour's governing body, the national executive committee, could offer a replacement statement of its own for the vote instead.

Corbyn said “there will be a clear vote in conference” on Brexit although he declined to specify whether there would be a clear vote on a second referendum.

“I don’t know what will come out of the compositing meeting,” he said, adding: “Let’s see what comes out of conference. I’m bound by the democracy of our party.”

Separately, a Corbyn ally, the Unite general secretary, Len McCluskey, said if there was a second referendum, remain should not be on the ballot paper, and that the public should choose between whether to endorse May’s final deal or opt for no deal at all.

“The referendum shouldn’t be on do we want to go back into the European Union?” McCluskey told the BBC’s Pienaar’s politics.