Labour leader Jeremy Corbyn will today tell MPs that the party will back a second referendum if their proposed Brexit deal is rejected on Wednesday.

Jeremy Corbyn will tell his MPs: "The Prime Minister is recklessly running down the clock, in an attempt to force MPs to choose between her botched deal and a disastrous No Deal. We cannot and will not accept.

"Last week, after our visit to talk to EU officials and leaders in Brussels and Madrid, no one can be in any doubt Labour's alternative Brexit plan is serious and credible. We are convinced our alternative, which puts jobs and living standards first, could command support in the House of Commons, bring people who voted Leave and Remain together, and be negotiated with the EU.

"That's why we will be putting down an amendment in parliament this week setting out Labour's plan: for a comprehensive customs union with a UK say; close alignment with the single market; guarantees on rights and standards; protection for Britain's role in EU agencies; and a security agreement which guarantees access to the European arrest warrant and vital shared databases. And we will be calling for legislation to underpin this mandate.

This week Labour will put its alternative plan for a vote in the House of Commons.

"We will also be backing the Cooper-Letwin amendment to rule out a No Deal outcome. One way or another, we will do everything in our power to prevent No Deal and oppose a damaging Tory Brexit based on Theresa May's overwhelmingly rejected deal.

"That's why, in line with our conference policy, we are committed to also putting forward or supporting an amendment in favour of a public vote to prevent a damaging Tory Brexit being forced on the country."

David Lammy, Labour MP for Tottenham and a supporter of the People's Vote campaign for a second referendum, said: "It is welcome news that the Labour Party is now, at long last, signalling it will accept the principle of giving the public the final say on Brexit.

"Even if MPs can agree some sort of deal, it would be wrong to force it on the British people when we now know so many of the promises made in 2016 have been broken and any deal will be worse than the one we've already got inside the EU.

"These are dangerous times for the Labour Party and our country. Jeremy Corbyn is today taking the first step to reunite our party by showing he is listening to our voters and members on this, the biggest issue of our time. But it is also crucial when food prices are already rising and car manufacturers are scrapping investment that we provide the clarity needed to plan for the future."

Liberal Democrats leader Sir Vince Cable said in a statement: "We welcome this news, this could be a defining moment in the Liberal Democrat campaign for a People's Vote.

"My party will work with Labour and others to secure a People's Vote with an option to remain.

"We have long argued it is the right and logical thing to do for the people to have the final say on Brexit.

"We welcome any MPs who share this crucial aim."