1 August 2019updated 07 Jun 2021 4:07pm

What will day one of a no-deal Brexit look like?

LONDON, ENGLAND - JANUARY 16: A general view of the Elizabeth Tower, commonly known as Big Ben and the Houses of Parliament on January 16, 2019 in London, England. The government suffered a historic defeat in the House of Commons last night as MPs voted 432 to 202 to reject Theresa May's Brexit Deal. Labour Leader Jeremy Corbyn immediately tabled a motion of no confidence in the government that will be debated and voted on later today. (Photo by Jack Taylor/Getty Images)

One of the questions I’ve been asking every European diplomat, policy wonk and British civil servant I can lately is: what happens if we leave the European Union on 31 October, a Thursday, and Parliament votes to accept the withdrawal agreement on the Friday? Or indeed the following Monday? What do the first 48 hours of a no-deal Brexit look like?

The reason why I think this question is important is because essentially, while a large majority of MPs oppose no deal, there is no majority in Parliament as of right now to do either of the things that could prevent it: to pass the withdrawal agreement as negotiated by Theresa May into law, or to revoke Article 50.

Mostly, the reaction is the same – EU diplomats simply don’t think that the matter will arise, and note that the likelihood is that while the structure of the agreement would remain essentially the same, it might well include yet more painful clauses about the future of Gibraltar and perhaps the Elgin Marbles, a Greek national treasure that the British government has long refused to return.

However, those clauses, no matter how bruising to national pride, won’t change the fact that there will be a large majority to bring a no-deal Brexit to a halt, but there will still only be one route to do that – an agreement that will be materially the same one as that rejected by Parliament on multiple occasions.

That’s one of the striking things in Sam Coates’ fantastic scoop for Sky News on the government document that lays out what the short-term reality of no deal could look like. The document contains a detailed assessment of what no deal could mean on the first day, within the first fortnight, and within the first month.

I’m not saying that, were I an MP worried both about no deal and about the consequences of revoking Article 50 I would think it a risk worth taking, not least because the answer from civil servants is that the known unknown of the first days of a no-deal Brexit is how bad the level of consumer panic is.

But it’s worth considering, when we think about the question of “how can a government be re-elected after going for a no deal Brexit, if all the experts are right about what that would mean?”, there’s another question we don’t know the answer to: “just how long have we had no agreement with the European Union for?”