The Labour leader said he would call a vote of no confidence in Boris Johnson’s government as soon as he could be “confident of success” in bringing the government down.
He would then use the 14 subsequent days to invite anti-no deal MPs in parliament to back him to lead a temporary government to ask the EU to delay Brexit, and to call a general election.
In a letter to opposition party leaders in Westminster and key Tory Brexit rebels including Dominic Grieve and Oliver Letwin, he said Labour would use that election to campaign for a second referendum which would include “an option to Remain”.
But the Liberal Democrats dismissed the Labour leader as being the right person to lead a temporary government, while Downing Street criticised him for planning to “overrule the referendum”.
It comes after Corbyn wrote to cabinet secretary Sir Mark Sedwill urging him to stop Johnson forcing through a no-deal Brexit in the middle of an election campaign. Corbyn said he had received a “non-committal” reply from Sedwill.
The PM has not ruled out delaying an election triggered by a vote of no confidence until after Brexit to fulfil his pledge that Britain will leave the EU “do or die” on Halloween.
In response, anti-no deal MPs are discussing the formation of a cross-party national unity government with a respected backbencher as PM, such as Letwin or Labour’s Hilary Benn.
But they fear that Corbyn’s refusal to back anyone but himself will scare Tory rebels away, as they would rather go through with a no-deal Brexit than put the Labour leader in Number 10.
In an attempt to reassure MPs reluctant to put him in Downing Street, Corbyn insisted he would not enact any Labour policies other than calling an election and delaying Brexit.
He wrote: “This government has no mandate for no deal, and the 2016 EU referendum provided no mandate for no deal.
“I therefore intend to table a vote of no confidence at the earliest opportunity when we can be confident of success.
“Following a successful vote of no confidence in the government, I would then, as leader of the opposition, seek the confidence of the house for a strictly time-limited temporary government with the aim of calling a general election, and securing the necessary extension of Article 50 to do so.
“In that general election, Labour will be committed to a public vote on the terms of leaving the European Union, including an option to Remain.”
The letter was sent to the SNP’s Ian Blackford, Liberal Democrat Jo Swinson, Plaid Cymru’s Liz Saville Roberts, the Green party’s Caroline Lucas, independent backbencher Nick Boles and Tories Grieve, Letwin and Caroline Spelman.
Swinson quickly scuppered some of Corbyn’s hopes by saying he was the wrong politician for the job
“Jeremy Corbyn is not the person who is going to be able to build an even temporary majority in the House of Commons for this task – I would expect there are people in his own party and indeed the necessary Conservative backbenchers who would be unwilling to support him. It is a nonsense,” she said.
Blackford welcomed the Labour leader’s letter and said the SNP would bring down the Tories in a no-confidence vote.
Saville Roberts also offered her cautious support, saying Plaid Cymru is open to a unity government regardless of who leads it, but that it must have “stopping Brexit” as its first priority.
Green Party MP Lucas also said she would back a no-confidence vote, but added that she wants Corbyn to guarantee Labour’s support for another MP to lead a temporary government if his bid to govern fails.
A No 10 spokesman said: “There is a clear choice: either Jeremy Corbyn as prime minister who will overrule the referendum and wreck the economy, or Boris Johnson as Prime Minister who will respect the referendum and deliver more money for the NHS and more police on our streets.”