BORIS Johnson’s hopes of getting his Brexit deal approved by MPS could be scuppered by a last-ditch Remainer plot that could force the PM to ask the EU for an extension.
Here’s what you need to know about the Letwin Amendment, which could see Brexit delayed for a further three months.
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The Letwin Amendment was put forward by Sir Oliver Letwin, pictured
What is the Letwin Amendment?
The Letwin Amendment was put forward by Sir Oliver Letwin, a Tory minister who had the whip removed in September.
It would withhold approval for Boris Johnson’s deal until Parliament has passed the necessary law to enact the agreement.
But crucially, that would trigger the Benn Act, which requires the PM to write a letter to the EU seeking a three-month extension.
Speaking with EU leaders at the EU Summit, Johnson tried to persuade MPs to back his deal by negotiating the removal of a deadline extension with European Commission President Jean-Claude Juncker.
But Mr Juncker said: We have a deal so why should we have a prolongation.
We have concluded a deal. So there is not an argument for delay. It has to be done now.
The PM has been adamant several times that he does not wish to ask for a deadline, but has said he will comply with the law if required.
Boris Johnson responds to questions after he delivered his statement on his new Brexit deal in the House of Commons
Sir Oliver Letwin MP listens as Prime Minister Boris Johnson delivers a statement in the House of Commons
What happens if the Amendment is passed?
If Letwins amendment is passed, the government will be required to request an extension from the EU under the Benn Act.
This would be because the Commons will not have approved Johnsons deal, regardless of whether he wins the 320 votes needed.
Sir Oliver has insisted that he is not seeking to scupper the PMs deal and has said he will support it today.
But he has said that MPs need the insurance policy of an extension in case the withdrawal legislation doesnt go through and the UK inadvertently crashes out of the EU with no deal.
In theory, it is still possible with the amendment that Brexit could be delivered by October 31.
If MPs in Commons back the Withdrawal Agreement Bill today and further support a meaningful vote on the PMs deal before October 31, it could be ratified by the deadline.
But the route to this could be made more difficult with the amendment in place.
What would the Amendment mean for Brexit?
It would effectively kick the can down the road on Brexit until the necessary legislation has been passed through Parliament, which would be the week after next at the earliest. And it would effectively make the highly-anticipated Commons showdown meaningless.
The move has a broad coalition of support from opposition parties and crucially by several of the sacked Tory rebels such as Philip Hammond and David Gauke. The move is designed to give an insurance policy to MPs who still fear a No Deal Brexit could happen on October 31.
Sir Oliver Letwin and other ex-Tory rebels fear hardline Brexiteer MPs will vote for the deal but then withdraw their support when the legislation is brought to the Commons next week.
If the deal passes today but the Government fails to pass the legislation by October 31 then Britain will leave the EU without a deal on Halloween. But the amendment has the benefit of also attracting support from MPs who want to reverse Brexit.
It would give Labour and other Remainer parties the chance to force through a second referendum as early as next week by attaching an amendment to the Brexit deal legislation.
Ex-Tory MP Stephen Hammond said the amendment was quite specific and designed to be non-contentious.
He said: “What it says is that Brexit doesn’t happen until all stages of the implementation bill are passed.
“What it is born out of is the concern that someone might choose to vote for tomorrow’s deal, thereby satisfying the Benn Act, and then choose to do something either by accident or by design which frustrates the implementation bill and then there is a possibility of us leaving the European Union without a deal.”