LONDON (AP) — British and European Union negotiators plan to work through the weekend to see if they can agree a Brexit deal in time for next week's summit of EU leaders.

The EU's chief negotiator, Michel Barnier, approved an intensification of the discussions after British Prime Minister Boris Johnson and his Irish counterpart, Leo Varadkar, said they could see a "pathway" forward following talks on Thursday.

European Council President Donald Tusk said Friday he could see the talks in Brussels going through the weekend, ahead of the EU summit, which starts Thursday.

The main stumbling block remains the border between Northern Ireland and Ireland, the United Kingdom's only land border with the EU. It has dominated talks ever since U.K. voters chose in 2016 to leave the EU.

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