Brussels (dpa) - The chief Brexit negotiator for the European Union said on Monday no significant progress had been made in trade negotiations with Britain over the weekend, EU diplomats told dpa, despite intense time pressure ahead of a year-end deadline.

The key areas of disagreement remained a level-playing field for competing businesses, fisheries and governance, top negotiator Michel Barnier told EU ambassadors.

After Barnier and his British counterpart David Frost called for a break in negotiations on Friday over a lack of progress, European Commission President Ursula von der Leyen and British Prime Minister Boris Johnson instructed them to continue their talks in Brussels.

Media reports claimed on Sunday evening that common ground on the issue of fisheries was close, but both sides promptly denied this.

France has threatened to veto a potential trade deal should the interests of its fishermen not be sufficiently respected.

Negotiations are set to continue on Monday, and von der Leyen and Johnson will take stock in a phone call in the evening.

Separately, a joint committee will discuss the implementation of their withdrawal agreement on Monday.

Britain formally left the European Union at the end of January, but remains in the single market and customs union until the end of the year. If there is no deal by this deadline, the harshest of tariffs and cumbersome custom checks would be reimposed.