The European Union and Britain saw their chances of reaching a full Brexit divorce deal by Thursday's EU summit diminish by the hour Wednesday as legal issues centering on the Irish border frustrated negotiators.
Hopes were increasingly turning toward getting a broad political commitment to a Brexit deal between British Prime Minister Boris Johnson and the 27 other EU leaders at this week's summit, with the legal details hammered out later.
That could mean yet another delay to Britain's departure, currently due to take place on Oct. 31. It also raises the prospect that the EU need to hold another Brexit summit before the end of the month.
"The 31st of October is still a few weeks away and there is a possibility of another summit before that if we need one," Irish Prime Minister Leo Varadkar said in Dublin.
The British government, meanwhile, insisted the U.K. would still leave the EU on Oct. 31 — but also promised to obey Parliament's order that it must seek a delay to Britain's Brexit departure date if no deal is in place by Saturday.
"I can confirm, as the prime minister has repeatedly set out, that ... the government will comply with the law," Brexit Secretary Stephen Barclay told British lawmakers on Wednesday.
The EU already struck a Brexit divorce deal with former British Prime Minister Theresa May, but that was rejected three times by British lawmakers. With that experience in mind, EU leaders are seeking reassurances from Johnson during this week's summit that he has the political weight to push any new deal through the House of Commons.
The Brexit talks plodded ahead Wednesday, further delaying preparations for the EU summit. Since the weekend, negotiators at the EU's glass-and-steel headquarters in Brussels have been locked into long sessions on how to deal with detailed customs, VAT and regulatory issues under British proposals to eliminate border checks between the U.K.'s Northern Ireland and EU member Ireland.
"Talks have been constructive but there still remains a number of significant issues to resolve," EU Commissioner Dimitris Avramopoulos said after being briefed by EU Brexit negotiator Michel Barnier.
Both sides were hoping that after more than three years of false starts and sudden reversals, a clean divorce deal for Britain leaving the bloc might be sketched out within the coming hours.
Johnson is eager to strike a deal at Thursday's summit that will let the U.K. leave the bloc in good order on Oct. 31, fulfilling his promise to get Brexit done, come what may.
U.K. lawmakers, however, are determined to push for another Brexit delay rather than risk a chaotic no-deal Brexit that economists say could hurt the economies of both the U.K. and the EU.
But both sides say gaps remain over plans for keeping goods and people flowing freely across the Irish border, the thorniest issue in the talks.
An open border between EU member Ireland and the U.K.'s Northern Ireland underpins both the local economy and the 1998 peace accord that ended decades of Catholic-Protestant violence in Northern Ireland. But once Britain exits, that border will turn into an external EU frontier that the bloc wants to keep secure.
The big question is how far Johnson's government is prepared to budge on its insistence that the U.K., including Northern Ireland, must leave the EU's customs union — something that would require checks on goods passing between the U.K. and the EU.
Ireland and other EU members say any checks on the Irish border are unacceptable.
The alternative is to have checks in the Irish Sea between Britain and Northern Ireland. But Northern Ireland's Democratic Unionist Party, the party that props up Johnson's minority Conservative government, strongly opposes any measures that could loosen the bonds between Northern Ireland and the rest of the U.K.
And even if there is a Brexit deal, it must be passed by both EU lawmakers and Britain's Parliament.
Pro-Brexit Conservative British lawmaker David Davis says success in passing a Brexit deal rests on the stance of the DUP.
"If the DUP says "This is intolerable to us' that will be quite important," he said.
DUP leader Arlene Foster said the party had not yet consented to a deal. She tweeted: "Discussions continue. Needs to be a sensible deal which unionists and nationalists can support."