Theresa May is seeking legal assurances in Brussels over the Northern Ireland backstop as she tries to strengthen non-binding EU language suggesting that the measure would only ever apply for “a short period”.
Speaking to reporters in the Belgian capital on Thursday a day after surviving a leadership challenge in which more than a third of Conservative MPs voted against her, Mrs May said: “I don’t expect an immediate breakthrough but what I do hope is that we can start to work as quickly as possible on the assurances that are necessary.”
Draft conclusions from an EU summit to be held later in the day suggest the bloc is ready to reassure the UK formally that the backstop to prevent a hard border in the island is an insurance policy that “does not represent a desirable outcome” and would only last for “as long as is strictly necessary”.
But EU officials have resisted the UK’s requests for statements to be given full legal force, and have insisted the bloc cannot in any way “contradict” or change the meaning of Britain’s withdrawal treaty.
The backstop has proved to be the big stumbling block to House of Commons approval of the withdrawal treaty because many Eurosceptic Conservative MPs loathe provisions that would keep the UK in a customs union with the EU and which neither side can end unilaterally.
The challenge for Mrs May is agreeing a side document that gives legal comfort on the implications of the withdrawal agreement without actually changing the treaty itself.
“What we are looking for is something called a joint interpretative instrument,” said a senior Whitehall figure. “It’s a codicil with legal force which means we won’t be stuck in the backstop.”
EU diplomats said that British negotiators initially looked at using the type of binding side deal that helped the Netherlands ratify an unchanged version of the EU-Ukraine agreement, even after voting against it in a referendum.
But for legal and political reasons, the UK is now examining a different form of “interpretative instrument”, used by the EU to convince the Belgian region of Wallonia to ratify the EU-Canada trade agreement in 2016. Under the Vienna Convention, such texts provide “context for the purpose of interpretation” of a treaty.
A senior minister said: “What we are trying to find is something that is justiciable, making clear the backstop isn’t permanent. But the problem is that the backstop is in the withdrawal agreement and has legal status. The danger is that you come up with a separate document but one that could be superseded by the treaty.”
Brussels is wary of entering into this kind of agreement with the UK in case the terms open the EU to legal challenge in future, for instance over the promises that the EU will negotiate in “good faith” on a trade deal so the backstop can be avoided.
Negotiators are discussing a two-step process. Mrs May would first receive some basic reassurances from EU leaders in Brussels on Thursday. She would then negotiate a fuller text in the run-up to a vote in the House of Commons, which she has promised to hold by January 21 after cancelling it this week.
Senior EU diplomats have warned London that making the assurances legally binding will limit the ability of the EU to offer “aspirational language” that diverges from the terms of the backstop in the withdrawal agreement.
Mrs May needs to come up with a concession on the issue not only to win over Conservative hard Brexiters but also Northern Ireland’s Democratic Unionist party, whose 10 members of parliament provide her minority government with vital parliamentary support.
The DUP fiercely opposes provisions in the backstop that would treat the province differently from the rest of the UK. But party officials said DUP leader Arlene Foster had a “useful” meeting with Mrs May on Wednesday afternoon on the issue ahead of the EU summit.
The officials said the prime minister “got the message” that “assurances on the backstop are not enough” and that the party needed to see changes in the withdrawal agreement itself.
“We emphasised that tinkering around the edges would not work,” Ms Foster said after the meeting. “We were not seeking assurances or promises. We wanted fundamental legal text changes.”
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