What is the Brexit backstop compromise?

Irish Prime Minister Leo Varadkar, left, shakes hands with EU chief Brexit negotiator Michel Barnier.

The draft deal on the Northern Ireland backstop, which was agreed last night by UK and EU officials (as I reported) - but not yet by the UK cabinet and EU 27 governments - would I think be acceptable to the DUP, the NI unionist party that props up May.

It includes a provision to massively increase checks on food and livestock flowing from the GB mainland to NI. But these happen already.

Importantly Michel Barnier, for the EU, has "de-dramatised" regulatory checks to the satisfaction of May, by agreeing there need not be any checks on goods flowing east-west across the Irish Sea to NI outside of the "marketplace".

Or to put it another way, the EU seems prepared to ignore the smuggling of a few dodgy TVs flowing from GB to NI to the European single market via the Republic of Ireland, after Brexit - largely because it thinks Irish officials would notice and take evasive action if lorry loads of screens were arriving in convoy.

Progress has been made in Brexit negotiations on the Irish border, one of the main sticking points in talks so far. Credit: PA

The big point is that if this is indeed what May and her cabinet attach their monikers to, the DUP should not cut up too rough. Because no new border would be introduced in the Irish Sea, even though an existing border for agri-foods would be reinforced.

But if the DUP is placated, I don’t remotely see how the Brexiter wing of May’s own party will be.

Because as I said last night, she and the EU appear to be as one that the UK would stay in the customs union - though they’ll find a different and deliberately obfuscatory nomenclature - unless and until some other system is put in place to deliver frictionless trade with the EU for the whole UK, including NI.

The big risk for the Brexiters stems from what the EU side sees as May’s capitulation (manifested by her negotiator Olly Robbins). Because they think she has decoupled sorting out the backstop and Withdrawal Agreement from sorting out the crucial detail of a future trading arrangement that would make said backstop otiose.

In other words they will fear the backstop would become the permanent arrangement - thus eliminating any possibility of the UK doing free trade deals with other countries and leaving the UK under the jurisdiction of the hated (by the Brexiters) European Court of Justice.

There will be the mother of all political explosions when the Withdrawal Agreement, including backstop, is leaked or published next week, ahead of the EU council.

Which is why it is being written, I am informed, in the kind of obscurantist style and language that only those with doctorates in semiotics and linguistics may be able to penetrate.

But if any cabal in history has the capacity to deconstruct quasi religious texts to prove they represent a conspiracy by a malign Brussels to subjugate Albion, it is of course the European Research Group of Tory Brexiters.

Theresa May’s battle for a Brexit made in her own image is only just beginning.