The man fronting the European Union's negotiations with the United Kingdom on a possible future trade deal has said time is running out.

Michel Barnier expressed disappointment at the lack of progress made on a deal to fill the void that will be left when the UK fully extricates itself from the bloc at the end of the year.

Barnier, the EU's chief negotiator, said he would like to see "genuine progress" made before June, as well as a decision from the UK on whether it wants to extend the transitional period beyond Dec 31. The transitional period, during which the nation follows EU rules and procedures despite its exit from the bloc on Jan 31, was designed to allow the two sides to continue frictionless trading until a replacement trade deal could be found.

But repeated delays in the UK's exit from the bloc ate into the transitional period. And, subsequently, the novel coronavirus outbreak, which left both Barnier and his opposite number battling symptoms, made negotiations all but impossible.

The BBC said Barnier believes only "limited progress" has been made and that he now wants talks to "move forward in a constructive fashion".

Two further rounds of negotiations－in May and June－are planned before the transitional period concludes on Dec 31, but Barnier said he wants the two sides to make a decision by June 30 on whether the transitional period should be extended to allow more time for talks.

The UK government has, however, repeatedly said it will not extend the transitional period, in part because the EU would charge a fee for the extension.

"The UK has affirmed once again… its wish to make tangible progress between now and June and we're on the same wavelength on this and we respect the same timetable," Barnier said. "That means that we need genuine progress by June if, at the end of this year, we want to strike an agreement which is commensurate to the level of our economic interdependence and geographical proximity."

But Barnier said the two sides are far from agreeing on the level of access the UK should expect to EU markets, and are at loggerheads on legal system cooperation, and how to manage their shared fisheries. The two sides are also understood to disagree on how future disputes should be reconciled.

Barnier said the EU will not agree to anything unless it is "balanced "and "sustainable". And he insists on a "level-playing field".

But he said "the UK did not wish to commit seriously on a number of fundamental points".

"The UK cannot refuse to extend transition and at the same time slow down discussions on important areas," he insisted.

A UK government spokesperson said: "We do not recognize the suggestion that we have not engaged seriously with the EU in any area. We have just had a negotiating round lasting most of a week, including two full days talking about fisheries and three full days discussing so-called level-playing-field issues."

The Mail Online noted the latest round of talks were the first for more than a month.

It said Barnier believes talks could collapse by June if progress is not made.