SUPPORTERS of a People's Vote on Brexit have dropped plans to table an amendment calling for a second EU referendum, blaming Jeremy Corbyn for failing to offer Labour’s backing.

Among supporters of the amendment were prominent Labour backbenchers Luciana Berger and Chuka Umunna and Conservative MP Sarah Wollaston, who chairs the influential Commons Liaison Committee.

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Ms Berger said: "Because the Labour leadership and frontbench won't back a People's Vote, there will not be a vote on the cross-party People's Vote amendment next week.

"This is not good enough. Labour should be clearly setting out a different course, not facilitating a job-destroying Brexit," declared the Liverpool MP.

Ms Berger added: "The Labour leadership has a really crucial role to play. The clock is ticking and, at this late stage, we 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 is now."

Dr Wollaston said that a People's Vote amendment could pass with the "unequivocal backing" of the Labour leadership.

"That is where we will get to eventually. Unfortunately, we are rolling ever closer to the edge of a cliff. The time for constructive ambiguity is over," insisted the MP for Totnes in Devon.

The Labour leader continues to resist calls to throw his party’s formal backing behind the People’s Vote campaign but has made clear that supporting a second EU vote remained “on the table” if the party was unable to force a general election.

The Liberal Democrats, meanwhile, have vowed to push ahead with their own amendment calling on the Government to prepare for a second referendum with the option of staying in the EU.

Tom Brake, the party’s Brexit spokesman, said: “There is still time to act in the national interest. Jeremy Corbyn and the Labour leadership must stop dreaming up more and more creative excuses for refusing to support a People’s Vote, which their members support and want.”

At present, the two amendments attracting most attention are those tabled by Labour’s Yvette Cooper and the Conservatives’ Andrew Murrison.

Ms Cooper’s seeks to extend the Article 50 process to the end of the year if Theresa May cannot agree a new deal with the EU by February 26. The aim is to prevent a no-deal Brexit.

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Whitehall appears to be particularly concerned about this one as it will involve a new bill and so, if passed, would be legally binding, which is not the case with the other amendments. The Yorkshire MP has used this route because the end of the Article 50 process, Brexit Day on March 29, is enshrined in law, so to change it another law has to be passed.

It is thought Ms Cooper and her allies, if the amendment is passed in next Tuesday’s Commons vote, are seeking to rush the new bill through the Commons in one day. However, procedurally, a problem could occur in the Lords, where there is no guillotine; the mechanism to curtail a debate. So, in theory, peers hostile to the Labour backbencher’s proposal could continue talking until a time it would cease to have an effect if passed.

The Government’s focus seems to be on defeating Ms Cooper’s amendment in the Commons. One argument will be that her measure sets a dangerous precedent whereby Government is no longer in control of parliamentary business, which could hobble this administration and future ones.

Mr Murrison’s amendment to time-limit the Irish backstop is expected to be backed by the Government. If passed, it would enable the Prime Minister to go back to Brussels to demand changes as the only way of getting a deal through Parliament, thus avoiding a no-deal outcome.

Of course, it is up to John Bercow, the Speaker, to decide which amendments he will allow to be debated and voted on. Last week, he rejected Mr Murrison’s amendment in favour of two others relating to the backstop, neither of which succeeded.

The SNP has yet to table its own amendment but will do so to put down a “marker”. However, it is also supporting the Cooper amendment. It believes there should be an extension to Article 50 to stave off a no-deal Brexit and provide time for a People’s Vote, which should include the option of staying in the EU.

By Thursday lunchtime, there were 14 amendments.

*Labour frontbench.

Backed by Jeremy Corbyn and his senior lieutenants, this would require time to be provided for Parliament to vote on options to prevent a no-deal Brexit, including Labour's preferred outcome - a permanent customs union, a strong single market relationship and alignment with the EU on rights and standards - and a second referendum.

*Second referendum.

Tabled by Lib Dem leader Sir Vince Cable and backed by all 11 of the party's MPs, this would require the Government to rule out a no-deal Brexit and make preparations for a second referendum, with Remain on the ballot paper.

*Citizens' assembly.

Tabled by Labour’s Stella Creasy and signed by a total of 25 Labour, Lib Dem and Green MPs, this would extend the two-year Article 50 negotiation process to allow the creation of a 250-member Citizens' Assembly to debate Brexit and make recommendations. This idea was championed by Gordon Brown, the former PM, last week.

*Indicative votes.

Tabled by Labour’s Hilary Benn, who chairs the Commons Brexit Committee, this would require a series of votes in Parliament on different options for Brexit to test support among MPs.

*Article 50 extension.

Backed by committee chairmen and women, including Mr Benn, Ms Cooper, Labour’s Rachel Reeves, and the Lib Dems’ Norman Lamb as well as senior backbenchers including Ed Miliband, the former Labour leader, and Sir Oliver Letwin, the former Tory Cabinet minister, this would require the Prime Minister to seek a delay to the planned Brexit date of March 29 if no deal has been approved by February 26.

*Power to Parliament.

Considered one of the proposals most likely to succeed, the plan tabled by Ms Cooper and former Conservative minister Nick Boles would force a vote on a bill giving Parliament control over the Brexit process if the PM fails to secure a deal by February 26. The bill would give MPs a vote on preventing a no-deal Brexit and extending Article 50.

*Grieve amendment.

Tabled by Dominic Grieve, the former Conservative Attorney General with cross-party backing from MPs, including former members of Mrs May's Government Justine Greening, Phillip Lee and Sam Gyimah, this would set aside six days in the run-up to March 29 for debate of Brexit proposals put forward by MPs.

*Free votes.

This proposal from Labour's Frank Field and Tory Ed Vaizey would require free votes on options, including the Irish backstop, a no-deal Brexit, Canadian and Norwegian models for relations with the EU, a customs union relationship and a second referendum to act as a "guide" for Government in future talks.

*Stop no-deal.

Drawn up by Midlands MPs Dame Caroline Spelman and Jack Dromey, with cross-party support from more than 110 MPs, this amendment rejects Brexit without a Withdrawal Agreement and Political Declaration on future UK/EU relations.

*Time-limited backstop.

Tabled by Mr Murrison and thought to be viewed sympathetically by the Government, this would put a deadline of December 31 2021 on the backstop arrangement required by the EU to avoid a hard border in Ireland. It is designed to give Mrs May additional negotiating clout by indicating to Brussels that this step might be enough to win parliamentary support for the Withdrawal Agreement reached last November.

*No backstop.

An amendment proposed by Conservative backbencher John Baron states that Parliament will not approve a Withdrawal Agreement which includes a backstop. Two further separate amendments tabled by the Basildon MP offer alternatives of a six-month time limit on the backstop or a requirement for the UK to have unilateral power to end it.

*Business Committee.

An amendment tabled by Mr Brake would establish a Business of the House Committee to govern the provision of parliamentary time for Brexit debates and legislation, including on a second referendum with Remain on the ballot paper. Mr Brake said the cross-party committee, with up to 17 members drawn from all parts of the UK, would put Parliament "in the driving seat of the Brexit process".