Hopes of a referendum on the final terms of Brexit are doomed to fail unless Jeremy Corbyn backs it, senior supporters have admitted.
Labour and Conservative MPs gathered on the steps of parliament to announce they would not be submitting a formal bid to get a second poll next week.
The campaigners had been expected to table an amendment to Prime Minister Theresa May’s “plan B” statement next Tuesday.
But Tory backbencher Dr Sarah Wollaston admitted that “until we have the leader of the opposition’s backing, it would not pass”.
Labour policy is to push for a general election before exploring other alternatives, which include a “People’s Vote”.
But after failing to win enough support for a “no confidence” vote to topple the prime minister, Mr Corbyn said pushing for an election “remains… the best outcome”.
He is now facing calls from 71 Labour MPs – around a third of the party’s presence in the House of Commons – to throw his weight behind another referendum.
Luciana Berger led the charge for Labour, accusing Mr Corbyn of “facilitating a job-destroying Brexit”.
She added that there was an “urgent need for leadership” and that Labour was “standing in the way” of its backers having the final say on Brexit.
“At this late stage, I appeal to Jeremy Corbyn to do the right thing by the majority of our voters, supporters and members and back a people’s vote.
“The time for action really is now.”
Ms Berger also dismissed the “handful of critics” among Labour ranks who have warned a second referendum risked undermining trust in democracy.
Last week, Labour MP Malnie Onn said the campaign was a “route” for Remainer MPs to “overturn” the decision to leave the EU in 2016.
She claimed “no work has been done to persuade Leave voters to change their minds” and there is an “over-reliance on demographic change”.
Prime Minister Theresa May has repeatedly ruled out calling another referendum, despite the deadlock in parliament over her Brexit deal.