In this Jan 30, 2020 file photo, a Pro-Europe supporter holds European Union (EU) and a British Union flags during a gathering by the cross party Pro-EU anti-Brexit group in Brussels, Belgium. (GEERT VANDEN WIJNGAERT / BLOOMBERG)

UK and European Union officials will resume face-to-face trade talks this weekend with Michel Barnier, the EU’s chief negotiator, warning that big disagreements between the two sides persist.

The UK is due to leave the EU’s single market at the year-end, with or without a trade deal in place, but negotiations between the sides have been deadlocked by disagreements in three key areas: access to British fishing waters, the level competitive playing field, and how any agreement will be enforced

Barnier told diplomats from the bloc’s 27 governments in a private meeting on Friday that he isn’t particularly optimistic about securing a deal, but he will continue to try for a few more days, according to officials with knowledge of the discussions. He will travel to London later in the day.

Barnier was forced to self-isolate last week after an EU official involved in the negotiations tested positive for the coronavirus. According to Les Echos, the Frenchman had warned David Frost, his British opposite number, that there was little point in him traveling to continue talks if the UK wasn’t prepared to give ground.

“My team and I are no longer in quarantine,” Barnier said in a Tweet. “Physical negotiations can continue,” he added, before warning that the “same significant divergences persist”.

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Barnier will also brief fishing ministers from the EU’s coastal states as part of his round of regular updates - but the meeting is significant because fishing rights have been a longstanding roadblock to a wider trade deal.

An accord could yet be reached as soon as next week, according to one EU official, though they cautioned that the bloc remains to be fully convinced that British Prime Minister Boris Johnson ultimately wants to sign up to an agreement. With no guillotine in sight, talks could even run on until the following week, the official said.

‘Mask-to-mask’

“Mask-to-mask talks will be held over the weekend - but this is not yet the last possible moment for a deal, and a deal can (by EU tradition) only occur at the last possible moment,” UBS Group AG Chief Economist Paul Donovan said in a note to clients on Friday.

Jamie Davies, a spokesman for Johnson, told reporters on Thursday that Britain is keen to intensify talks and reach a deal with the bloc.

READ MORE: EU leaders urged to step up preparations for no-deal Brexit

The UK is due to leave the EU’s single market at the year-end, with or without a trade deal in place, but negotiations between the sides have been deadlocked by disagreements in three key areas: access to British fishing waters, the level competitive playing field, and how any agreement will be enforced.

One official said the two sides are still struggling to agree on ratchet clauses - rules to ensure the UK’s environmental and labor standards evolve in a similar way to the EU’s - and on how any deal should be enforced.

On Wednesday, French Foreign Minister Jean-Yves Le Drian accused the UK of stalling discussions with the bloc and warned the two sides were still “extremely far apart” on the issue of fishing.