European Union chief Brexit negotiator Michel Barnier, right, and the British Prime Minister's Europe adviser David Frost arrive for Brexit trade talks between the EU and the UK, in Brussels, Aug 21, 2020. (YVES HERMAN / POOL PHOTO VIA AP)

The European Union (EU) and United Kingdom raised serious doubts about the chances of striking a deal on their future relationship after a testy week of negotiations that saw little progress.

The two sides are stuck in several areas, notably EU access to British fishing waters and the so-called level playing field requirements aimed at preventing a distortion of competition, both of which need to be part of any agreement

“At this stage an agreement between the UK and the EU seems unlikely,” the bloc’s chief negotiator Michel Barnier said after talks broke up on Friday. “Too often this week it felt as if we were going backwards more than forwards.”

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The two sides are stuck in several areas, notably EU access to British fishing waters and the so-called level playing field requirements aimed at preventing a distortion of competition, both of which need to be part of any agreement. Failure to get a deal would see them trading with tariffs and quotas and a breakdown of cooperation on scores of issues.

“We have had useful discussions this week but there has been little progress,” David Frost, the UK’s Europe adviser, said in a statement released as Barnier was talking. “Agreement is still possible, and it is still our goal, but it is clear that it will not be easy to achieve.”

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The UK tried to unlock the deadlock this week by submitting a confidential draft of the final deal, setting out where the major differences remain. The EU had resisted doing this, saying the two sides were still too far away on the fundamental issues.

After a slow start as the coronavirus pandemic struck, there was a burst of optimism in June after Prime Minister Boris Johnson convinced the EU side that he was serious about getting a deal. But the positivity has ebbed as the negotiators have been unable to bridge the biggest divides.