Boris Johnson will hold a vote in the House of Commons on Monday calling for a general election to be held on December 12.
However, the prime minister’s hopes of securing the early poll that he seeks will not be realised if, as seems likely, Labour leader Jeremy Corbyn refuses to give him the necessary support.
Mr Johnson has already tried twice in his premiership to persuade MPs to back an early election under terms set out in the 2011 Fixed-Term Parliaments Act.
On both occasions last month, he fell well short of getting the necessary two-thirds of MPs — 434 out of 650 — to back the move, as required by the legislation. The main reason why Mr Corbyn would not back an election was because he feared it could open the way to a no-deal Brexit ahead of the October 31 deadline.
Mr Johnson is now trying to win Labour round a third time. On this occasion, the prime minister believes there are two new factors that could make it much harder for Mr Corbyn to refuse his request.
The first is the likelihood that the EU will decide to allow an extension of Britain’s membership of the bloc until January 31.
EU officials are hoping that member states will clarify their position on an extension as soon as Friday, when national ambassadors meet in Brussels. European Council president Donald Tusk’s push for a January 31 extension has won widespread support among EU capitals, but not all countries’ positions are settled.
If a three-month extension is granted, the Conservatives will argue that a no-deal Brexit will be impossible before a December 12 election — and that Mr Corbyn’s previous objections have been overcome.
The second new factor confronting Mr Corbyn is that Mr Johnson is now tying the need for an election to the full passage through parliament of the Brexit deal that he signed last week with the EU.
Mr Johnson said in a letter to the Labour leader on Thursday night that if a December 12 election were approved by MPs, parliament would have to be dissolved by November 6.
The prime minister also said he would “make available all possible time” between now and November 6 for the withdrawal agreement bill implementing the Brexit deal to be discussed and voted through its parliamentary stages — taking Britain out of the EU before polling day.
Despite this offer, Mr Corbyn on Thursday night looked set to reject Mr Johnson’s proposal.
The Labour leader is likely to use the argument that much more time is needed to get the Brexit legislation — with its immense implications for Britain’s future — through the Commons.
However, Downing Street officials are making clear that the government will not proceed with further parliamentary debate on the withdrawal agreement bill unless an election date has been approved by MPs.
“Once you agree on an election date, you have a deadline by which the parliamentary debate on Brexit has to come to an end,” said one of Mr Johnson’s aides. “If you don’t have that election deadline, Labour can string out the debate for ever and this country gets held hostage.”
Assuming Labour rebuffs Mr Johnson’s move on Monday, Number 10 will be left with few options. The prime minister could try to bring a one-line bill to the Commons that legislates that an election must be held on December 12. This would require a straight majority of MPs to support it.
Such a bill would have to be rushed through all its legislative stages in the Commons and the House of Lords to be on the statute book by November 6, enabling an election on December 12.
If that fails, then all the signs are that the political process will be completely stuck.
Mr Johnson would be likely to accuse Labour of cowardice for failing to back an election at least three times. But Mr Corbyn is expected to retort that the prime minister is “playing games”.
The outcome, however, is that parliament would be paralysed. Asked whether this would mean that Britain would end up with a zombie parliament, a Downing Street official said on Thursday night: “It already is a zombie parliament.”
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