The Prime Minister wanted MPs to formally back his deal today but a proposal put forward by Sir Oliver Letwin to ruin the premier’s hopes of making Brexit progress was passed by 322 votes to 306.
The amendment will now force the PM to ask the EU for a Brexit delay under the terms of the anti-No Deal law known as the Benn Act.
The amendment does not kill off Mr Johnson’s deal and it will still be possible for him to deliver Brexit by October 31.
But the path to fulfilling his ‘do or die’ Halloween pledge will now be fraught with difficulty and the chances of a Brexit delay have increased exponentially.
Here is a breakdown of what is likely to happen now the amendment has been backed by MPs.
What happens tonight now the Letwin amendment has been agreed by MPs?
The PM will have to comply with the Benn Act and send a letter to the EU asking for a Brexit delay.
He would then likely bring forward the Withdrawal Agreement Bill – the legislation needed to actually make Brexit happen – on Monday this week to try to crash it through Parliament as quickly as possible.
If he was able to get MPs and peers to agree to the draft legislation in the coming days he would then be able to hold the ‘meaningful vote’ on his deal, paving the way for the UK to leave the EU on time.
Boris Johnson, pictured in the House of Commons today, is urging MPs to formally back his proposed Brexit deal
But the PM’s hopes of making Brexit progress could be scuppered by an amendment put forward by Sir Oliver Lewtin which has cross-party support
What happens to Boris Johnson’s deal?
The Prime Minister’s deal will still be alive and he could deliver Brexit by October 31 but he will have to put his agreement into law first.
The amendment would withhold support for the PM’s deal until such a time as the government has brought forward and passed the Withdrawal Agreement Bill.
By failing to agree to a Brexit deal by close of play today, the provisions outlined in the Benn Act would be triggered and the PM would have to ask the EU to push back the current departure date.
The amendment would effectively postpone the ‘meaningful vote’ on the accord until the government has got its Withdrawal Agreement Bill through Parliament.
The thinking is that by withholding support for the deal until the key Brexit legislation is in place, MPs will further protect against the possibility of the UK leaving the EU without a deal on October 31.
Some Remainers are suspicious that if MPs back the PM’s deal today and there is no extension, Brexiteers who want a No Deal split could then scupper the passage of the laws needed to deliver an orderly exit, causing a bad break on Halloween.
How likely is it that MPs and peers will agree to the Withdrawal Agreement Bill?
The Letwin amendment will effectively rob the PM of the chance to test whether there is a majority for his deal.
That means that nobody will know for certain whether there is a majority in favour of the so-called WAB.
Even if there is a majority it is likely to be a slim one which will make the passage of the legislation incredibly difficult as rebel MPs potentially try to amend and change it.
Draft laws have been rushed through parliament in quick time before but whether something as divisive as the legislation to deliver Brexit could be dealt with equally as swiftly is unclear.
What happens if the PM is able to get the Brexit law agreed and win a ‘meaningful vote’ before October 31?
The UK could still leave the EU on the current timetable but the closer we get to Halloween the tougher that becomes and the chances of a delay increase.
If the PM can get the deal signed off by MPs by the end of the coming week – a big if – his ‘do or die’ pledge could still be stuck to.
But anything beyond that and time will get extremely tight because once MPs have agreed the deal it still has to go through the European Parliament.
What is the EU likely to do?
If the amendment is agreed and the PM sends the Brexit delay letter the EU will have to decide whether to offer an extension.
The most likely scenario is that the bloc will keep its powder dry and not formally respond until it has seen whether the PM can win a vote in the Commons this coming week on the Withdrawal Agreement Bill.
If he can, then Brussels will probably hold fire on offering an extension on the grounds that the UK could still agree to a deal and leave on time.
If he cannot win a vote on the WAB this week and his deal looks dead then the bloc will face more pressure to make a final decision on any delay.
It is thought in such circumstances the bloc would offer a postponement in order to stop a No Deal Brexit.
That would pave the way for a general election potentially being held before the end of the year.
Could the EU refuse to grant a delay?
Yes. Emmanuel Macron and Leo Varadkar have both suggested that they are against any further delay but Angela Merkel reportedly said an extension would be inevitable if the deal is rejected.
It is possible that the EU could decide to cuts its losses on the grounds that the Brexit stalemate has gone on for too long.
But such a move appears unlikely because it would result in the bloc taking the blame for a No Deal split.
Could there be an emergency EU summit?
If the PM is able to make progress in the coming days and win a vote on the WAB but he is unable to get everything done by the end of the week there could then be an emergency summit held in Brussels on October 28.
If the PM’s deal is still alive but more time is needed to get it through Parliament European leaders could agree to a short extension.