Parliament is sitting on a Saturday for the first time in 37 years to debate and vote on Boris Johnson’s Brexit deal – here is what to expect.
What is happening?
MPs began their special session at just after 09:30 BST.
Peers started their debate at 10:00 and are due to finish at 15:00.
Commons proceedings got under way with a statement from Prime Minister Boris Johnson and a response from Labour leader Jeremy Corbyn.
The prime minister took questions on his Brexit deal from MPs for nearly two hours and this was followed by a debate. They have finished the debate and are now voting.
What time will voting get under way?
The voting has now started.
There could be up to four votes.
Commons Speaker John Bercow has selected two amendments to be voted on by MPs.
- Former Conservative MP Sir Oliver Letwin’s proposal to withhold approval for the deal unless and until legislation implementing it is passed
- A cross-party amendment rejecting a no-deal Brexit and seeking a second referendum
The first vote is on the Letwin amendment – it could turn out to be the only vote taken on Saturday.
It was due to be followed by a vote on the main government motion – whether or not to back the deal.
But the government does not want this vote to happen if MPs back the Letwin amendment, as it could delay Brexit.
It is not clear at this stage how they would prevent the vote happening – it’s possible Tory MPs could decline to take part and will be sent home by party managers.
But the motion has already been tabled and the government can not “pull” the vote on it.
Downing Street says that even if MPs back the main government motion, with the Letwin amendment, it could not be seen as a vote in favour of a deal, because the amendment says: “This House has considered the matter but withholds approval unless and until implementing legislation is passed.”
If the vote on the Brexit deal does take place, and MPs reject it, we could then move to votes on a second government motion on whether or not there should be a no-deal Brexit.
Before a vote takes place on that, MPs could get a chance to vote on the cross-party amendment rejecting a no-deal Brexit and seeking another referendum.
MPs would then vote for a fourth time – on the government no-deal motion. We know there is a majority in the Commons against a no-deal Brexit, so this would be unlikely to pass.
What happens if the Letwin amendment passes?
It means a deal will not have been approved by 2300 so, under the terms of the Benn Act, the prime minister must send a letter to Brussels requesting a three month Brexit delay.
But regardless of what happens on Saturday, the government has said it plans to push ahead with the legislation enacting the treaty agreed by Boris Johnson in Brussels – the Withdrawal Agreement Bill.
They plan to hold the second reading of that bill on Tuesday, which would give MPs a chance to register their support – or not – for Boris Johnson’s Brexit deal.
What happens if MPs vote for the deal?
If the government motion is passed by MPs without being amended, it will just be the first stage of getting the deal into law.
The government is likely to want to move quickly so it can meet Boris Johnson’s 31 October deadline.
The Withdrawal Amendment Bill, which implements the legally-binding treaty, will be presented to Parliament early next week – something the government now plans to do whatever happens in Parliament on Saturday.
How can you follow the debate?
You can find out the latest developments on the BBC News website and app, where we’ll have live coverage in text and video, and analysis from our experts.
There will also be coverage on BBC Two from 13:15 to 16:30, and continuous coverage on the BBC News Channel.
There will also be extended editions of BBC News at Six and News at Ten, as well as a special edition of BBC Newsnight.
Why is the Letwin amendment significant?
By the BBC’s Parliamentary Correspondent Mark D’Arcy
The government seems to be all but conceding that the Letwin amendment will pass, and is making its dispositions accordingly – announcing plans to hold a “meaningful vote” on the Withdrawal Agreement Bill on Tuesday.
This would corner MPs into a Yes/No vote on their deal, and given there are a fair number of Labour rebels, the government could well win.
Certainly, the vote would put any number of Labour MPs – and MPs for other parties – from Brexit-voting constituencies in a very awkward place.
Watch out for an attempt to attach a second referendum to the deal in some way.
But the success of that effort would require full-throated support (and whipping of their MPs) from the Labour Party. They are not there yet, and they may never be.
If the government wins a “meaningful vote” on Tuesday, the legislation to underpin the new deal would then go forward – and that would provide further opportunities to attempt amendments.
Winning the next meaningful vote is only the beginning of a new phase of Brexit; it’s not even the beginning of the end.