Eurosceptics described the climbdown as a “bitter betrayal” even as the PM’s own partners in Government, the DUP, appeared to reject the deal Number 10 and Brussels have thrashed out.

Negotiators for Britain and the EU have drawn up an outline exit agreement containing a number of new compromises, which the two sides had been hoping to sign off and publish this evening.

However, a commitment to continued “regulatory alignment” between the North and South of Ireland designed to break the deadlock has angered the unionist DUP, putting the deal in jeopardy.

Already SNP leader Nicola Sturgeon and the Mayor of London Sadiq Khan have pounced upon the compromise to suggest that Scotland and the capital should also get a special deal with the EU.