The latest round of negotiations between the EU and UK on the future relationship have ended prematurely, with both chief negotiators issuing downbeat statements on progress.

In a statement Michel Barnier, the EU's chief negotiator, said: "After four days of discussions, serious divergences remain."

His counterpart David Frost said in a separate statement that the negotiations had been "comprehensive and useful" but that they had "also underlined the significant differences that still remain between us on a number of important issues".

It is understood that there has been little or no progress on the four key stumbling blocks. These remain the so-called level playing field, fisheries, police and judicial cooperation and the governance issue, or how disputes will be resolved in future.

These were the first face-to-face negotiations since the first round at the beginning of March, with 16 officials travelling from London to Brussels to meet their counterparts on the key negotiating "tables".

Officials have stressed that this was not a full negotiating round and have downplayed the fact that the negotiations ended today and not tomorrow as envisaged.

Mr Barnier said in his statement that the EU had "listened carefully" to prime minister Boris Johnson during his video conference with the heads of the main EU institutions on 15 June, and to his reiteration of the UK's red lines.

He said: "The EU expects, in turn, its positions to be better understood and respected in order to reach an agreement. We need an equivalent engagement by the United Kingdom."

Mr Barnier repeated the EU's position that there would be no agreement without "robust guarantees for a level playing field including on state aid to ensure open and fair competition among our businesses; a balanced, sustainable and long-term solution for our European fishermen and women; an overarching institutional framework and effective dispute settlement mechanisms".

Mr Frost, however, said the UK still hoped to reach an "early understanding" of the principles underlying an agreement before the end of July.

The statements have undermined a degree of optimism expressed ahead of this week's talks that the new format of intensified negotiations, endorsed by Boris Johnson and the heads of EU institutions, might start to break the deadlock.

Sources suggest there was very little movement on the key issues this week.

"We are really trying to find compromises as much as possible bearing in mind our red lines, and we felt the UK wasn't really engaging on their side," said one EU source.