The future of Brexit will be shaped this week as the UK enters a critical phase in its departure from the EU.
You may have heard that one before but this time it really is true: hang on to your hats, it’s going to be a bumpy few days.
Officially, Britain is due to leave the bloc with or without a deal on Friday.
Prime Minister Theresa May hopes, however, that the EU will grant Britain a flexible extension - or “flextension” - to June 30 as she and Labour leader Jeremy Corbyn attempt to thrash out a Brexit compromise.
Here is how the week will play out.
Will May and Corbyn do a deal?
As last week drew to a close, negotiations between Labour and the government appeared to be on the brink of collapse.
Shadow Brexit Secretary Keir Starmer fumed May was not “countenancing any change” to her thrice-rejected withdrawal agreement and Labour put out a statement deeming talks “disappointing”.
In a video address on Sunday afternoon, however, the PM underlined she recognised that “as it stands” her deal did not command the support of a majority of MPs, signalling perhaps that she was ready for compromise.
Corbyn wants the UK to stay in a customs union with the EU, as well as seeking a “strong single market deal”.
Both are committed to ending free movement, protecting manufacturing jobs and avoiding a hard border in Ireland, and have said so publicly.
It is claimed, therefore, that little divides them on policy. What could throw a spanner in the works is the politics.
A majority of Tory MPs are vehemently opposed to a customs union and Corbyn is facing a Remainer rebellion, with his MPs bitterly divided over whether any deal the pair strike must include a “confirmatory public vote” - which is code for a second referendum.
What happens if talks collapse?
The PM has said that if the pair cannot agree on a unified deal, the Commons will be given a series of Brexit options to vote on, similar to the indicative votes process which has just concluded without any agreement.
Could we crash out of the EU without a deal?
In short: by accident, yes we could.
On Monday, the House of Lords will continue considering a bill brought by Sir Oliver Letwin and Yvette Cooper, which is key.
Introduced last week after MPs seized control of the parliamentary agenda, the bill could let the Commons decide the length of any extension offered to the UK by the EU.
If the bill is passed by the Lords on Monday it will go for Royal Assent. But if there are amendments, it will probably be considered again by the Commons on Monday night.
May could, at this juncture, outline her own plans to the Commons and lay a government motion about the extension to Article 50.
The Letwin-Cooper bill was somewhat overtaken by May’s letter to the European Council President Donald Tusk on Friday setting out the UK’s demand for a flexible extension to June 30, with the option to pull out whenever a deal is secured.
But the real control over the UK’s departure date lies in the hands of the European Council, who meet on Wednesday.
Will the EU let us delay Brexit if we need to?
All 27 leaders who make up the council must agree an extension. May will travel to Brussels to make her case to them after PMQs on Wednesday.
Tusk has recommended a long extension of a year, with a break clause for the UK to pull out at any time should a deal be done.
There is some division among EU leaders on whether to offer an extension, heightening fears of no-deal.
French President Emmanuel Macron is among those sceptical of offering any delay to Brexit at all without the UK having a “clear plan”, given the bitter divisions which have been on display in the Commons.
Should the EU agree to an extension, however, May will bring what she has been offered straight back to the Commons on Thursday.
It’s not clear what could happen if MPs reject it.
Downing Street has warned the Cooper-Letwin bill could cause an “accidental no-deal Brexit” on Friday - Britain’s updated Brexit day after May’s deal was voted down - because MPs could reject the extension date on offer when May returns.
Given the strength of opposition to no-deal, however, it is likely MPs will band together to agree a long extension, though the political implications are hard to judge and the public reaction could be fierce.
Does all this mean the UK holds European Parliament elections?
This we do not yet know.
Elections to the European Parliament are due to be held on Thursday May 23.
If Brussels and Westminster agree on either a “flextension” to June 30 or for a year, it may be irrelevant if it is certain that Britain will not be an EU member state by then.
Brussels may also insist Britain takes part in the poll as part of any extension.
May has said she will make “responsible preparations” if there is no other option, though the move is strongly opposed by Brexiteers, and Labour has already begun searching for candidates, with deputy leader Tom Watson saying he regarded the poll as “inevitable”.
Should the UK withdraw from the bloc shortly after candidates are elected, the poll will have cost the UK in excess of £100m.