Tom Watson has ramped up the pressure on Jeremy Corbyn, with a demand Labour wholeheartedly back a second referendum saying: “Our hearts are Remain”.
In a keynote speech on Monday to the Centre for European Reform, Watson will say Labour’s members and its values had always been pro-European.
He will argue the only way to break the Brexit deadlock at Westminster, is to put the issue back to the people in a new public vote in which Labour would campaign “proudly” for Remain.
Corbyn has been resisting pressure to fully embrace a second referendum, amid heavy criticism of the party’s dismal showing in last month’s European elections.
Confusion over its position, supporting another referendum in certain limited circumstances, was widely blamed for a poor performance which saw it beaten into third place behind the Brexit Party and the Liberal Democrats.
In his speech, Watson will say there is still time to reverse the Brexit vote, but only if Labour is fully behind a second referendum.
“Pro-European is who we are and who we have always been. Our members are Remain. Our values are Remain. Our hearts are Remain,” he will say.
“The only way to break the political deadlock is to bring the public back into this decision and we must argue strongly to remain.
“Our future doesn’t need to be Brexit. We can change our future. We can put Britain back at the heart of Europe again.
“We can be proud of leading the fight for a fairer and stronger future, together. But we can only achieve this future if Labour fights for it and champions it. It’s time we do that.”
Watson is likely, however, to face a strong push-back from allies of Corbyn, determined to resist any change of policy.
Last week party chairman Ian Lavery hit out at Remainers in the party, dismissing them as “left wing intellectuals” who were “sneering at ordinary people” in traditional Labour heartlands who voted for Leave.
However Watson will say that all strands of of opinion within the party were entitled to a hearing.
“We cannot go on dismissing one another’s right to speak and questioning one another’s motives and intentions,” he will say.
“Some people have begun to equate support for Europe with class identity, I don’t think that’s right or helpful.
“The majority of Labour people are supportive of Europe - and that support is not dictated by social class.”
He will argue that the “core” EU values of internationalism, solidarity and freedom were also the values of Labour.
“I’m a European democratic socialist. I don’t love Europe despite being socialist, I love Europe because I am a socialist,” he will say.
“Democratic socialism is achieving common causes by the strength of collective endeavour. That’s what Europe is.”