Both sides now face the prospect of beginning a crunch summit on Wednesday without a draft divorce deal, increasing the chances of a disorderly and damaging British departure from the bloc.
Dublin:
Last-ditch talks on Sunday between London and Brussels' chief Brexit negotiators failed to reach an agreement on trade rules for Northern Ireland, EU representative Michel Barnier said.
"We met today Dominic Raab and UK negotiating team. Despite intense efforts, some key issues are still open, including the backstop for IE/NI to avoid a hard border," Barnier tweeted, referring to EU member Ireland and the British province of Northern Ireland.
Barnier added that he would brief the European Parliament and the leaders of the EU member states, who will arrive in Brussels on Wednesday for a dinner on the eve of their October summit.
Diplomatic sources confirmed that a meeting of the "diplomatic sherpas" -- senior officials from EU members -- that had been planned for Monday to review a draft deal has been cancelled.
"The commission informed the ambassadors that no deal was reached today. There will be no further negotiations until the summit," one source said, speaking on condition of anonymity.
Other sources familiar with Barnier's meeting with EU ambassadors confirmed this, and one diplomat added that "certain countries insisted that preparations for a 'no deal' be accelerated."