UK Prime Minister Theresa May has announced that a vote on a deal reached with the European Union to exit the bloc will not be held on Tuesday as scheduled, recognizing that she faced rejection “by a significant margin.”

“It is clear that while there is broad support for many of the key aspects of the deal, on one issue, the Northern Ireland backstop, there remains widespread and deep concern,” May said in a speech to Parliament. “We will therefore defer the vote schedule for tomorrow and not proceed to divide the house at this time.”

While May said that she would seek assurances from the EU on the Northern Ireland issue, EU officials have insisted that the deal as it stands is the final offer.

From the standpoint of domestic UK politics, the agreement satisfies few. The deal would see the UK continue to be bound be certain key EU regulations, angering Brexiteers, while at the same time losing privileges, leading Brexit opponents to wonder why the initiative is not abandoned altogether.

The European Court of Justice, meanwhile, handed down a ruling on Monday concluding that the UK could unilaterally withdraw its notice to leave the EU.

“That article allows that Member State — for as long as a withdrawal agreement concluded between that Member State and the European Union has not entered into force… to revoke that notification unilaterally, in an unequivocal and unconditional manner,” the decision stated.