Boris Johnson’s gamble on an early election looks set to flop, after opposition parties signalled they will block a poll so long as a no-deal Brexit remains possible.

The prime minister dramatically issued a demand for a 12 December election after abandoning his “do-or-die” pledge to take the UK out of the European Union by Halloween.

Mr Johnson offered to allow MPs extra time to debate and ratify his Brexit deal by 6 November if they approved the UK’s first December election in almost 100 years. But aides said he would pull the Withdrawal Agreement Bill altogether if they refuse.

But Labour whips issued an instruction to the party’s MPs to abstain in Monday’s vote, effectively meaning Mr Johnson needs a substantial rebellion by the opposition to force his plan through.

The PM requires a two-thirds majority of the 650 MPs in the Commons to trigger the election. With 434 votes needed and only 288 Conservatives in the Commons, he will need around 150 opposition MPs and independents to join him.

Mr Johnson said it would be “morally incredible” if Labour blocked the election for a third time.

People's Vote march – demanding vote on final Brexit deal Show all 30 1 /30 People's Vote march – demanding vote on final Brexit deal People's Vote march – demanding vote on final Brexit deal Mandatory Credit: Photo by Guy Bell/REX (9725259aq) Marching down Whitehall - People's March for a People's Vote on the final Brexit deal. Timed to coincide with the second anniversary of the 2016 referendum it is organised by anti Brexit, pro EU campaigners. People's March for a People's Vote, London, UK - 23 Jun 2018 Guy Bell/REX Rex People's Vote march – demanding vote on final Brexit deal Demonstrators carry banners and flags as they participate in the People's March demanding a People's Vote on the final Brexit deal, in central London on June 23, 2018, the second anniversary of the 2016 referendum. Tens of thousands of people demonstrated in London on Saturday calling for a second vote on Britain's departure from the European Union. / AFP PHOTO / Niklas HALLE'NNIKLAS HALLE'N/AFP/Getty Images NIKLAS HALLE'N AFP/Getty Images People's Vote march – demanding vote on final Brexit deal A young protestor shouts as she takes part in the People's Vote demonstration against Brexit Getty Images People's Vote march – demanding vote on final Brexit deal A woman holds a placard as she joins EU supporters, calling on the government to give Britons a vote on the final Brexit deal, participating in the 'People's Vote' march in central London, Britain June 23, 2018. REUTERS/Henry Nicholls HENRY NICHOLLS Reuters People's Vote march – demanding vote on final Brexit deal epa06833888 Pro-EU demonstrators take part in a People's March anti-Brexit rally in Parliament Square in London, Britain, 23 June 2018. Protesters are calling for a referendum on the final deal. The protest is taking place on the second anniversary of the Brexit referendum. EPA/ANDY RAIN ANDY RAIN EPA People's Vote march – demanding vote on final Brexit deal A protester's pro-EU t-shirt EPA People's Vote march – demanding vote on final Brexit deal epa06833892 A pro-EU demonstrator waves a European Flag during a People's March anti-Brexit rally in Parliament Square in London, Britain, 23 June 2018. Protesters are calling for a referendum on the final deal. The protest is taking place on the second anniversary of the Brexit referendum. EPA/ANDY RAIN ANDY RAIN EPA People's Vote march – demanding vote on final Brexit deal Demonstrators carry banners and flags as they participate in the People's March demanding a People's Vote on the final Brexit deal, in central London on June 23, 2018, the second anniversary of the 2016 referendum. Tens of thousands of people demonstrated in London on Saturday calling for a second vote on Britain's departure from the European Union. / AFP PHOTO / Niklas HALLE'NNIKLAS HALLE'N/AFP/Getty Images NIKLAS HALLE'N AFP/Getty Images People's Vote march – demanding vote on final Brexit deal epa06833960 Tens of thousands of people march through London during a People's March anti-Brexit demonstration in London, Britain, 23 June 2018. Protesters are calling for a referendum on the final deal. The protest is taking place on the second anniversary of the Brexit referendum. EPA/ANDY RAIN ANDY RAIN EPA People's Vote march – demanding vote on final Brexit deal Leader of the Liberal Democrats, Vince Cable speaks during the People's March demanding a People's Vote on the final Brexit deal, in central London on June 23, 2018, the second anniversary of the 2016 referendum. Tens of thousands of people demonstrated in London on Saturday calling for a second vote on Britain's departure from the European Union. / AFP PHOTO / Niklas HALLE'NNIKLAS HALLE'N/AFP/Getty Images NIKLAS HALLE'N AFP/Getty People's Vote march – demanding vote on final Brexit deal epa06833964 A young pro-EU demonstrator takes part in a People's March anti-Brexit rally in Parliament Square in London, Britain, 23 June 2018. Protesters are calling for a referendum on the final deal. The protest is taking place on the second anniversary of the Brexit referendum. EPA/ANDY RAIN ANDY RAIN EPA People's Vote march – demanding vote on final Brexit deal Gina Miller and Caroline Lucas EPA People's Vote march – demanding vote on final Brexit deal epa06834044 Tens of thousands of people march through London during a People's March anti-Brexit demonstration, in London, Britain, 23 June 2018. Protesters are calling for a referendum on the final deal. The protest is taking place on the second anniversary of the Brexit referendum. EPA/ANDY RAIN ANDY RAIN EPA People's Vote march – demanding vote on final Brexit deal epa06833264 Thousands of people march through London during a People's March anti Brexit demonstration in London, Britain, 23 June 2018. Protesters are calling for a referendum on the final deal. The protest is taking place on the second anniversary of the Brexit referendum. EPA/ANDY RAIN ANDY RAIN EPA People's Vote march – demanding vote on final Brexit deal Tens of thousands of people march through London EPA People's Vote march – demanding vote on final Brexit deal epa06833265 Thousands of people march through London during a People's March anti Brexit demonstration in London, Britain, 23 June 2018. Protesters are calling for a referendum on the final deal. The protest is taking place on the second anniversary of the Brexit referendum. EPA/ANDY RAIN ANDY RAIN EPA People's Vote march – demanding vote on final Brexit deal Demonstrators at the People's Vote March Getty People's Vote march – demanding vote on final Brexit deal 'Two months too young to decide on my future' REUTERS People's Vote march – demanding vote on final Brexit deal Crowds taking part in the People's Vote march for a second EU referendum at Trafalgar Square in central London. PRESS ASSOCIATION Photo. Picture date: Saturday June 23, 2018. See PA story POLITICS Brexit. Photo credit should read: John Stillwell/PA Wire John Stillwell PA People's Vote march – demanding vote on final Brexit deal A young girl joins in the march PA People's Vote march – demanding vote on final Brexit deal An EU flag is draped across the statue of Winston Chruchill in Parliament Square REUTERS People's Vote march – demanding vote on final Brexit deal Demonstrators gather prior to the start of the People's March demanding a People's Vote on the final Brexit deal, in central London on June 23, 2018, on the second anniversary of the 2016 referendum. / AFP PHOTO / Niklas HALLE'NNIKLAS HALLE'N/AFP/Getty Images NIKLAS HALLE'N AFP/Getty Images People's Vote march – demanding vote on final Brexit deal Vince Cable MP, Pro-EU campaigner Gina Miller, Tony Robinson and Caroline Lucas MP join with crowds PA People's Vote march – demanding vote on final Brexit deal Crowds gather on Pall Mall in central London, during the People's Vote march for a second EU referendum. PRESS ASSOCIATION Photo. Picture date: Saturday June 23, 2018. See PA story POLITICS Brexit. Photo credit should read: John Stillwell/PA Wire John Stillwell PA People's Vote march – demanding vote on final Brexit deal Crowds gather on Pall Mall PA People's Vote march – demanding vote on final Brexit deal A man resembling Britain's Foreign Secretary Boris Johnson, joins EU supporters Reuters People's Vote march – demanding vote on final Brexit deal EU supporters, calling on the government to give Britons a vote on the final Brexit deal, participate in the 'People's Vote' march in central London, Britain June 23, 2018. REUTERS/Henry Nicholls HENRY NICHOLLS Reuters People's Vote march – demanding vote on final Brexit deal People gather in Trafalgar Square REUTERS People's Vote march – demanding vote on final Brexit deal Pro-EU campaigner Gina Miller and Tony Robinson PA People's Vote march – demanding vote on final Brexit deal EU supporters, calling on the government to give Britons a vote on the final Brexit deal, participate in the 'People's Vote' march REUTERS

But after a hastily organised meeting of shadow cabinet ministers, Jeremy Corbyn said that he would not countenance an election while no-deal Brexit remains a possibility.

“We are not resisting the chance to have an election, we want an election because we want to take our case to the people of this country,” said the Labour leader.

“But we do not want this country to be in any danger of crashing out of the EU without a deal because of all the damage it will do to jobs across this country.”

Many Labour MPs are fiercely opposed to granting Mr Johnson an election at a time when Tories have no majority in the Commons but are leading the polls by double-digit margins and Corbyn’s party is scraping along around 25 per cent – less than Michael Foot recorded in the disastrous 1983 ballot.

One shadow cabinet source told The Independent: “We’d lose half the parliamentary party if we back it.”

Speaking shortly after a surprise cabinet meeting in 10 Downing Street, Mr Johnson said that an election offered an opportunity to both complete EU withdrawal and install a new government by Christmas.

“The way to get Brexit done is to be reasonable with parliament and say if they genuinely want more time to study this excellent deal, they can have it, but they have to agree to a general election on 12 December.,” he said.

But opposition parties made clear they did not trust the prime minister to ensure a no-deal Brexit was avoided. Under electoral laws, the motion for Monday’s vote cannot include the proposed election date, leaving Mr Johnson to announce it after he has secured permission to dissolve parliament.

A Downing Street source said that – despite having secured a majority at second reading for his Withdrawal Agreement Bill – if he is denied an election on Monday, the prime minister will make no further attempt to force his Brexit deal through parliament by the new 31 January deadline expected to be offered by the European Union on Friday.

Instead, he would table only a bare minimum of legislation in parliament and focus the government’s efforts on pushing for a general election by whatever means are available. These could potentially include a bill to override fixed-term parliaments legislation or even a vote of no confidence in his own government. Chancellor Sajid Javid announced he has cancelled the budget planned for 6 November.

“The worry is that parliament will just waste the next three months the same way they have wasted the last three years,” said the source. “The Labour Party can’t try to keep this country hostage by saying they are not going to vote for this deal but they are not going to be held accountable to the electorate.”

In a letter to Corbyn, the prime minister said that if the date was approved, the government would make as much time available as possible up to 6 November to scrutinise and pass the Withdrawal Agreement Bill, including weekends and extended sitting hours. It is understood the government is ready to order another Saturday sitting this weekend to get the process under way.

The PM’s announcement came despite deep division within the cabinet and among his No 10 advisers over the wisdom of going to the country before EU withdrawal is complete.

Ministers including Julian Smith, Nicky Morgan and Matt Hancock were thought to be wary of an onslaught from Nigel Farage’s Brexit Party costing Tories the votes of Leave-backers frustrated at the PM’s failure to hit his Halloween deadline.

A ComRes poll taken on 16-17 October suggested the recent Tory poll lead could vanish if Brexit is delayed beyond 31 October, with 27 per cent saying the would back Labour, against 26 per cent for Conservatives and 20 per cent for Mr Farage’s party.

But Mr Johnson’s powerful aide Dominic Cummings has argued for an early poll, which he believes will allow Conservatives to secure a working majority on the back of a “people vs the parliament” message.

If approved in Monday’s vote, the Johnson election would be the first in December since 1923. MPs raised concern about the willingness of activists to campaign and voters to turn out in potentially cold, wet and dark conditions. It has the potential merit for Conservatives of falling during university holidays, when students may not be as committed to voting.

Mr Johnson made clear that if his Brexit bill is not passed by 6 November, he will fight the election campaign on a plea to voters to give him the kind of majority he needs to allow him to ratify his deal in the New Year and take the UK out of the European Union by the end of January.

In his letter to Mr Corbyn, Mr Johnson wrote: “This parliament has refused to take decisions. It cannot refuse to let the voters replace it with a new parliament that can make decisions.

“Prolonging this paralysis into 2020 would have dangerous consequences for businesses, jobs and for basic confidence in democratic institutions, already badly damaged by the behaviour of parliament since the referendum. Parliament cannot continue to hold the country hostage.”

SNP leader Nicola Sturgeon indicated her party would oppose an election: “Johnson appears to be saying to MPs ‘If you vote for an election, I’ll bring back my bad Brexit bill and try to drag us out of the EU before we go to the polls’.

“Elections should be exercises in letting voters decide, not devices for charlatans to get their own way.”

And Liberal Democrat leader Jo Swinson said: “Boris Johnson is trying to distract from his government’s failure. He has missed his do-or-die deadline and is now demanding that parliament give him a general election and the time to ram through his Bill without proper scrutiny.