EU and UK Brexit negotiators have paused talks until after this week's EU summit. Amid some speculation that officials would confirm a provisional Brexit deal on Sunday, the Northen Irish issue got in the way, again.
British Brexit Minister Dominic Raab and EU chief negotiator Michel Barnier left protracted Brexit negotiations on hold on Sunday, with the issue of how to resolve the border between Northern Ireland and the Republic of Ireland still the main sticking point.
After a hastily arranged meeting late on Sunday with Raab in Brussels, Barnier tweeted that key issues remained open.
The British government said in a statement on Sunday night that there were still "unresolved issues," but added the negotiators had made "real progress" toward an agreement.
The deadline for a Brexit deal is fast approaching. Brussels hoped to have a provisional deal in place this month, which could be signed off by EU leaders at their next summit in November.
On Saturday, business website Bloomberg reported that British and EU officials had agreed to extend the 21-month transition period that kicks in following Brexit in March 2019.
The transitional phase keeps Britain within the EU's single market and customs union, but London would lose its direct influence on policy-making in Brussels.
Citing diplomats familiar with the situation, Bloomberg said the transition extension until the end of 2021 — which would only be enacted if trade talks slowed — would help overcome the last major hurdle in Brexit talks, namely the Irish border issue.
Northern Ireland is the key
Theresa May's Conservative government and the EU have spent months trying to find a solution to ensure frictionless trade post-Brexit at the UK's only land border with the EU, between the British territory of Northern Ireland and the Republic of Ireland.
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During 18 months of Brexit negotiations, Brussels has demanded a backstop to ensure the border would remain open even if the EU and the UK were unable to agree a new permanent trade deal.
The transition extension would almost certainly ensure that the Brussels backstop proposal, where Northern Ireland remains within the EU's customs union and single market after Brexit, will never be enacted.
May has insisted that she would never agree to the EU's proposal, which would separate Northern Ireland constitutionally and economically from the rest of the UK.
May faces more Brexit rebellion
The British prime minister, who relies on support from a tiny Northern Irish group — the Democratic Unionist Party (DUP) — for her parliamentary majority, faces strong resistance from the DUP to any deal that leaves the territory under the EU's jurisdiction.
May must also overcome considerable opposition to her Brexit plan from within her own party. Several members of her cabinet, and as many as 80 of her MPs, are hard-line Brexiteers, who have lobbied hard for looser ties with the EU following Brexit.
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May will need support from the opposition Labour party to ensure the Brexit agreed with Brussels passes her own parliamentary vote.
Before March next year, the European Parliament also needs to ratify any Brexit deal.