Why will Boris Johnson turn into a pumpkin at the stroke of midnight? The EU’s chief negotiator has set that as a deadline for the British prime minister to offer his concessions on the Irish border in writing. It’s the last minute, almost literally, before the EU meetings that could possibly accept a revamped Brexit deal before the Hallowe’en deadline.

And even that might not work if Johnson can’t sell Parliament on the necessary concessions:

Michel Barnier has set Boris Johnson a midnight deadline to concede to EU demands and agree to a customs border in the Irish Sea or be left with nothing to take to the Commons.

According to sources, the EU’s chief negotiator told ministers that without a major move there was little prospect of a deal being signed off by leaders at a summit on Thursday, before a special sitting of the UK parliament on Saturday.

Don’t get your hopes up, either. While Johnson has discussed some potential concessions, he’s put nothing in writing yet. Until that happens …

Legal text had yet to be tabled by the British negotiators, Barnier told ministers in Luxembourg. He advised the EU capitals he would announce on Wednesday whether negotiations on an agreement would have to continue into next week.

Barnier warned that the starting point for a deal has to be the Northern Ireland-only backstop, keeping it in the EU’s single market for goods and erecting a customs border in the Irish Sea, a proposal previously rejected by Theresa May.

It’s a proposal that will get immediately rubbished by the DUP too, which is why May had to reject it in the first place. The DUP provides the Tories what little claim they still have to a parliamentary majority, and they have made clear in the past few days that their position has not changed. Northern Ireland has to get treated exactly the same as the rest of the UK or it’s no deal.

Still, hope springs eternal, and Barnier told the media earlier that anything is possible:

VIDEO: The European Union's Brexit negotiator says even if a deal will be difficult, "it is still possible this week." The U.K. Brexit secretary says talks are ongoing and "we need to give them space to proceed." Read the full story here: https://t.co/33A38UzBWe pic.twitter.com/XksFogC9Qj

— AP Europe (@AP_Europe) October 15, 2019

Time is running out, however, and an agreement would need to include the complete legal text — not just conceptual agreement. That might make this the thirteenth hour more than the eleventh:

A senior German official wouldn’t rule out a Brexit agreement in principle by Wednesday afternoon, but stressed the importance of the specifics — and how time consuming they will be to work out.

“The basis for our decisions are legal texts in which the details are settled,” the official, who briefed reporters on condition of anonymity in line with department rules, said in Berlin. “But there has been progress, and as always in these negotiations the biggest progress happens over the final meters.”

Late Monday, Dutch Foreign Minister Stef Blok said the British proposals to keep the Irish border protected from smuggling and fraud once it leaves the bloc were insufficient.

“The U.K. proposal contained some steps forward but not enough to guarantee that the internal market will be protected,” Blok said.

Word around the UK campfire will be that Johnson will publish a proposal by tomorrow, and that it will attempt to eat his cake whilst having it too:

It is understood that the negotiating teams have agreed in principle that there will be a customs border down the Irish Sea. A similar arrangement was rejected by Theresa May as a deal that no British prime minister could accept.

Johnson will still have to win over parliament – including the Democratic Unionist party (DUP) and the hardline Tory Brexiters in the European Research Group – on the basis that, under the deal, Northern Ireland will still legally be within the UK’s customs territory.

“Northern Ireland would de jure be in the UK’s customs territory but de facto in the European Union’s,” one diplomatic source said of the tentative agreement.

The prime minister will be able to boast that the UK “whole and entire” has left the European Union.

That’s, um, pretty much what the EU offered two years ago. May might have gone for it if she hadn’t gambled on a snap election and wound up in the DUP’s debt. Will the DUP allow Johnson to save face by agreeing to this rhetorical compromise but major functional concession? I’d call it doubtful at best.

For now, the safe bet is that Johnson turns into a pumpkin at midnight. And then the question becomes whether he can legally cross over the border on Hallowe’en or whether he becomes subject to agricultural inspections. Heyyy-yoooooo ….