Labour could back a People’s Vote to stop more MPs defecting, after the party was rocked by nine resignations in one week.
Shadow chancellor John McDonnell said Labour had kept the option on the table, and added ‘we’re moving towards that’.
Labour’s position, thrashed out at the party’s conference last year, keeps open the option of a People’s Vote if Theresa May is unable to get a deal through parliament and there is not a general election.
But the leadership appears to have been against a People’s Vote – with reports that Jeremy Corbyn’s team even took out mentions to a second referendum in his latest letter to Theresa May.
McDonnell told the Evening Standard: ‘On the People’s Vote, we’ve kept it on the table and we’re moving towards that.’
He said Labour was ‘moving into implementation stages around our conference decision, around the People’s Vote’.
A compromise plan put forward by Labour MPs Peter Kyle and Phil Wilson could present a route to the party supporting a vote.
The two MPs have devised a plan to support the prime minister’s Brexit deal on the condition it is put to a confirmatory public vote.
The Commons could be asked to vote on the Kyle-Wilson amendment before the end of February.
McDonnell said that any referendum would include an option to Remain as an alternative to Theresa May’s deal.
‘If we were going on a People’s Vote based on a deal that has gone through parliament in some form, if that got voted down then you’d have status quo, and that would be Remain,’ he said.
The shadow chancellor said that if it was an option ‘I’d campaign for Remain and I’d vote for Remain’.
A spokesman for the People’s Vote campaign said: ‘It looks like Labour will test whether its Brexit plan has the support of Parliament next week.
‘It deserves scrutiny but, with the prime minister effectively ruling out a customs union, John McDonnell and other senior Labour figures recognise there will be only one option left for them which is in line with party policy.
‘If they back compromise proposals to put any final Brexit deal to the people, it will help unite their party, as well as avoid the catastrophe for their constituents of a no-deal departure from the EU.’