More than 50 Labour candidates have signed a pledge to back remain in a new referendum after Jeremy Corbyn said voters would be left in the dark on how the party would campaign until spring.

Prominent pro-EU MPs seeking re-election such as David Lammy and Margaret Beckett underlined their commitment to fighting to stay in the EU, with more signatures expected ahead of the election on 12 December.

If elected, Labour will seek to negotiate a new Brexit deal with greater protections for workers, before putting that deal to the public in a Final Say referendum.

But Mr Corbyn has refused to confirm whether his top team could campaign for different outcomes until after the negotiations have taken place.

Senior shadow cabinet figures such as Sir Keir Starmer and Diane Abbott made it clear they would campaign for remain in another referendum.

Best pictures from Final Say Brexit march Show all 76 1 /76 Best pictures from Final Say Brexit march Best pictures from Final Say Brexit march Crowds march through central London Getty Best pictures from Final Say Brexit march People's Vote Final say march - 19 October 2019 Angela Christofilou Angela Christofilou/The Independent Best pictures from Final Say Brexit march Protesters gather in Parliament Square Led By Donkeys Best pictures from Final Say Brexit march Mayor of London Sadiq Khan joins protesters PA Best pictures from Final Say Brexit march People's Vote Final say march - 19 October 2019 Angela Christofilou Angela Christofilou/The Independent Best pictures from Final Say Brexit march People's Vote Final say march - 19 October 2019 Angela Christofilou Angela Christofilou/The Independent Best pictures from Final Say Brexit march People's Vote Final say march - 19 October 2019 Angela Christofilou Angela Christofilou/The Independent Best pictures from Final Say Brexit march People's Vote Final say march - 19 October 2019 Angela Christofilou Angela Christofilou/The Independent Best pictures from Final Say Brexit march Anti-Brexit protesters fill Parliament Square in London PA Best pictures from Final Say Brexit march People's Vote Final say march - 19 October 2019 Angela Christofilou Angela Christofilou/The Independent Best pictures from Final Say Brexit march People's Vote Final say march - 19 October 2019 Angela Christofilou Angela Christofilou/The Independent Best pictures from Final Say Brexit march People's Vote Final say march - 19 October 2019 Angela Christofilou Angela Christofilou/The Independent Best pictures from Final Say Brexit march People's Vote Final say march - 19 October 2019 Angela Christofilou Angela Christofilou/The Independent Best pictures from Final Say Brexit march People's Vote Final say march - 19 October 2019 Angela Christofilou Angela Christofilou/The Independent Best pictures from Final Say Brexit march People's Vote Final say march - 19 October 2019 Angela Christofilou Angela Christofilou/The Independent Best pictures from Final Say Brexit march People's Vote Final say march - 19 October 2019 Angela Christofilou Angela Christofilou/The Independent Best pictures from Final Say Brexit march People's Vote Final say march - 19 October 2019 Angela Christofilou Angela Christofilou/The Independent Best pictures from Final Say Brexit march People's Vote Final say march - 19 October 2019 Angela Christofilou Angela Christofilou/The Independent Best pictures from Final Say Brexit march People's Vote Final say march - 19 October 2019 Angela Christofilou Angela Christofilou/The Independent Best pictures from Final Say Brexit march A demonstrator marches EPA Best pictures from Final Say Brexit march People's Vote Final say march - 19 October 2019 Angela Christofilou Angela Christofilou/The Independent Best pictures from Final Say Brexit march People's Vote Final say march - 19 October 2019 Angela Christofilou Angela Christofilou/The Independent Best pictures from Final Say Brexit march People's Vote Final say march - 19 October 2019 Angela Christofilou Angela Christofilou/The Independent Best pictures from Final Say Brexit march Protesters push a float depicting Dominic Cummings using Boris Johnson as a puppet during the Final Say Brexit march in London PA Best pictures from Final Say Brexit march EU supporters react after the result of the vote on the deal delay was announced at the House of Commons REUTERS Best pictures from Final Say Brexit march A demonstrator carries his dog draped in EU flag AP Best pictures from Final Say Brexit march Thousands of people taking part in a People's Vote march AFP/Getty Best pictures from Final Say Brexit march Protesters use their flags to shelter from the rain Getty Images Best pictures from Final Say Brexit march Protesters march towards Parliament Square Getty Images Best pictures from Final Say Brexit march Anti-Brexit demonstrators carry placards and EU flags AP Best pictures from Final Say Brexit march Sir Oliver Letwin MP in Parliament Square, London, during an an anti-Brexit, Let Us Be Heard rally, after it was announced that the Letwin amendment, which seeks to avoid a no-deal Brexit on October 31, has been accepted PA Best pictures from Final Say Brexit march Thousands of people taking part in a People's Vote march UK BROADCASTERS POOL/AFP via Get Best pictures from Final Say Brexit march A protester with "Bollocks to Brexit" stickers on his head Getty Images Best pictures from Final Say Brexit march Demonstrators march EPA Best pictures from Final Say Brexit march Britain's main opposition Labour Party shadow Secretary of State for Exiting the EU Keir Starmer, shadow Home Secretary Dianne Abbott, shadow Chancellor of the Exchequer John McDonnell, shadow Foreign Secretary Emily Thornberry speaks on stage in Parliament Square AFP via Getty Images Best pictures from Final Say Brexit march Anti-Brexit supporters cheer outside parliament AP Best pictures from Final Say Brexit march A EU supporter waves flags REUTERS Best pictures from Final Say Brexit march Anti-Brexit supporters AP Best pictures from Final Say Brexit march Protesters shout and chant demanding a final say Getty Images Best pictures from Final Say Brexit march Police look towards protesters Getty Images Best pictures from Final Say Brexit march Pro-Brexit protesters outside the Houses of Parliament in London PA Best pictures from Final Say Brexit march People taking part in an Anti-Brexit, Let Us Be Heard march head to Parliament Square in London PA Best pictures from Final Say Brexit march People taking part in an Anti-Brexit, Let Us Be Heard march in Trafalgar Square PA Best pictures from Final Say Brexit march Anti-Brexit supporters cheer outside parliament AP Best pictures from Final Say Brexit march People taking part in an Anti-Brexit, Let Us Be Heard march past Trafalgar Square PA Best pictures from Final Say Brexit march Protesters shout and chant Getty Images Best pictures from Final Say Brexit march Cory (7) sits on his father's shoulders as protesters march towards Parliament Square Getty Best pictures from Final Say Brexit march People attend the 'Together for the Final Say' march EPA Best pictures from Final Say Brexit march Protesters march towards Parliament Square Getty Images Best pictures from Final Say Brexit march Mayor of London Sadiq Khan speaks on stage PA Best pictures from Final Say Brexit march A woman in EU costume EPA Best pictures from Final Say Brexit march Anti-Brexit protesters fill Parliament Square in London PA Best pictures from Final Say Brexit march Anti-Brexit protesters AP Best pictures from Final Say Brexit march Anti-Brexit protesters hold an Independent banner Angela Christofilou/The Independent Best pictures from Final Say Brexit march Protesters hold an anti-Brexit placard by The Independent stall during the Final Say Brexit march in London Tom Richell Best pictures from Final Say Brexit march Anti-Brexit protesters in Parliament Square, London, PA Best pictures from Final Say Brexit march Demonstrators hold placards and EU flags AFP/Getty Best pictures from Final Say Brexit march An anti-Brexit protester joins in the Final Say Brexit march on 19 October AP Best pictures from Final Say Brexit march EU supporters march in London REUTERS Best pictures from Final Say Brexit march Sir Patrick Stewart and Paul McGann join in the Final Say Brexit march in London on 19 October PA Best pictures from Final Say Brexit march EU supporters march Reuters Best pictures from Final Say Brexit march A demonstrator shouts into a megaphone as she marches AFP via Getty Images Best pictures from Final Say Brexit march A dog dressed in an anti-Brexit placard is walked in the Final Say Brexit march in London EPA Best pictures from Final Say Brexit march EU supporters march REUTERS Best pictures from Final Say Brexit march A morris dancer takes part in the Final Say Brexit march in London PA Best pictures from Final Say Brexit march Whippets are dressed in EU flag clothing during the Final Say Brexit march in London AP Best pictures from Final Say Brexit march Protesters march towards parliament in the Final Say Brexit march in London on 19 October 2019 PA Best pictures from Final Say Brexit march An anti-Brexit demonstrator takes part in the Final Say Brexit march in London AFP/Getty Best pictures from Final Say Brexit march EU supporters call on the government to give Britons a vote on the final Brexit deal Reuters Best pictures from Final Say Brexit march Anti-Brexit protesters Angela Christofilou/The Independent Best pictures from Final Say Brexit march An anti-Brexit protester Angela Christofilou/The Independent Best pictures from Final Say Brexit march Anti-Brexit protesters demonstrate in London during the Final Say Brexit march on 19 October AP Best pictures from Final Say Brexit march Protesters push a float depicting Dominic Cummings using Boris Johnson as a puppet during the Final Say Brexit march in London AFP/Getty Best pictures from Final Say Brexit march Protesters march towards parliament from Park Lane in the Final Say Brexit march in London on 19 October 2019 PA Best pictures from Final Say Brexit march Marchers visit The Independent stall during the Final Say March in London Tom Richell Best pictures from Final Say Brexit march An anti-Brexit protester holds a sign calling for a Final Say during a march in London EPA

The party’s stance aims to appeal to both sides of the Brexit divide – but it risks leaving Labour vulnerable to the Liberal Democrats who are campaigning to scrap Brexit entirely.

Wes Streeting, who is battling to be re-elected in Ilford South, said: “It’s important to be honest with voters about where I stand before the general election.

“I have always fought for them to have the final say on Brexit and I continue to believe that we’re much better off remaining in the EU.”

Alison McGovern, standing in Wirral South, said she was clear that every kind of Brexit was “negative for Britain”.

“We need a new agenda for remaining and reforming Britain and the EU, and that is why people should vote Labour in this General Election,” she told The Independent.

Some Labour candidates are also under pressure from electoral pacts by the Liberal Democrats, the Greens and Plaid Cymru, who are uniting behind a single candidate in some 60 seats.

Jo Stevens faces a Lib Dem candidate in Cardiff Central after the Greens bowed out – despite being a long-standing campaigner for another public vote.

She tweeted: “My track record as a leading pro remain MP is clear. Cosy deals between other parties just opens the door to Johnson and his hard Brexit Tories.

“They were second in Cardiff Central in 2017. Shows that this isn’t about making sure we remain at all​.”

Thangam Debbonnaire is another Labour candidate facing a challenge from a Remain pact, this time in Bristol West.

She told The Independent: "I know that remaining in the EU is the best option for Bristol West and have consistently promoted this as my preferred option. Therefore I will campaign for remain.

"But it is right for the other option to be a Labour deal based on Labour values, because if the UK votes again to leave, it's vital that it is on terms which protect rights and protections and jobs and trade, rather than undermine them all, as both Tory deals have done and leaving with no deal does even worse.

Therefore I support Labour offering a public vote, negotiating a Labour deal to put on the ballot paper versus remaining in the EU, and asking the people to have the final say."

Andrew Lewin, founder of Remain Labour, which co-ordinated the letter, said Mr Corbyn's party offered the best route to staying in the EU.

He said: “The party is already committed to putting Brexit back to the people and I am delighted that more than 50 parliamentary candidates have already pledged to campaign to remain in the EU in all circumstances.

“Remain voters want to vote for the Labour party with confidence at this election. Our pledge will help candidates in England, Scotland and Wales to underline that the Labour party is the strongest remain alliance in the country.”

At a campaign event in Harlow, Essex, earlier this week, Mr Corbyn said his strategy was to try to “bring people together” over Brexit.

He said: “Our conference in September in Brighton came together and agreed that position.”

The Labour leader added: “At the conclusion of those three month negotiations, we will hold a special conference of our party in a democratic way. We will come to a view as a party.