Boris Johnson has signalled he will table an "almost identical" general election plan to that put forward by the SNP and Liberal Democrats, should MPs reject his call for a December 12 vote.

The Prime Minister will attempt to call an early general election in a Commons vote on Monday evening.

However, under the Fixed-Term Parliaments Act (FTPA), he requires a two-thirds majority to vote with him to trigger an election - a total of 434 MPs - with Labour MPs ordered to abstain.

But the SNP and Liberal Democrats are also pushing for a pre-Christmas election, with the two parties tabling a tightly-drafted Bill to call an election on December 9.

The parties say this Bill would restrict Johnson's ability to get his Brexit deal through the Commons before the election and would also prevent him from fiddling with the election date.

The motion would only need a simple majority of MPs to pass, although it could fall prey to Commons amendments.

A Downing Street source said: "Tonight is Labour's last chance to have an election with Brexit done - they can vote tonight for the 12th and get Brexit done before parliament is dissolved.

"If not, we will introduce a Bill almost identical to the SNP Bill tomorrow and we will have a pre-Christmas election anyway.

"This parliament has repeatedly failed to respect its promise to respect the referendum.

"Millions of families and businesses can't plan because of constant delays.

"We need a new parliament by Christmas so we can get Brexit done in January and the country can move on."

Lib Dem sources said they would need to see any Bill brought forward by the government before deciding whether to support it.

Earlier on Monday, Brussels accepted the UK's request for a so-called "flextension" until January 31 - enabling Britain to leave the bloc sooner if the Withdrawal Agreement Bill (WAB) becomes law.

Johnson has previously said he would prefer to be "dead in a ditch" than miss the October 31 deadline.

SNP Westminster leader Ian Blackford said the Prime Minister had "failed".

He said: "Crucially, we've now been given time by Europe.

"We're not leaving the European Union on October 31 so Boris Johnson has failed in his plans to take us out.

"We've got that extension until the end of January. We need to use the time to best effect."

Blackford added: "Parliament has not been able to resolve this.

"Let's put it back to the people, let's have a general election, let's dissolve the House of Commons this week and have an election on December 9.

"We don't want to go too far into the Christmas period."