THE UK's chief negotiator says "little progress" has been made at the end of the seventh round of talks to broker a post-Brexit trade deal with the EU.

In a statement, David Frost said: "As I said last week, agreement is still possible, and it is still our goal, but it is clear that it will not be easy to achieve.

"Substantive work continues to be necessary across a range of different areas of potential UK-EU future co-operation if we are to deliver it.

"We have had useful discussions this week but there has been little progress."

Chief negotiator David Frost accused the EU of making negotiations "unnecessarily difficult" by "insisting" the UK must sign up to the bloc's state aid and fisheries policy.

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"The EU is still insisting not only that we must accept continuity with EU state aid and fisheries policy, but also that this must be agreed before any further substantive work can be done in any other area of the negotiation, including on legal texts," he said in a statement.

"This makes it unnecessarily difficult to make progress. There are other significant areas which remain to be resolved and, even where there is a broad understanding between negotiators, there is a lot of detail to work through. Time is short for both sides."

The EU's chief Brexit negotiator Michel Barnier has said the issue of a level playing field "is not going to go away".

Speaking at a press conference following the latest round of talks, Barnier said: "Ladies and gentlemen, the need for a level playing field is not going to go away, even if the UK continues to exist on a low-quality agreement on goods and services only."

He added that "it is a non-negotiable pre-condition to grant access to our market of 450 million citizens".

Barnier said: "We are asking for nothing more but nothing less, nothing less than what Prime Minister Boris Johnson committed to in our joint political declaration last October together with the 27 EU leaders."

Barnier added that the UK and EU negotiators have made "no progress whatsoever" on the issue of fisheries.

He said: "We hear the British Government's concern about maintaining its sovereignty and its regulatory autonomy and we respect that, clearly. But no international agreement was ever reached without the parties agreeing to common rules - no international agreement.

"And I can predict, with absolute certainty, this will also be the case of trade agreements between the UK and other partners in the future such as the United States, Japan and Australia.

"Apart from the question of a level playing field there are still many other areas where progress is needed and for example, obviously fisheries where we have made no progress whatsoever on the issues that matter."

Barnier added that other areas where more progress is needed include law enforcement "where we still struggle to agree on the necessary guarantees to protect citizens' fundamental rights and personal data".

He continued: "And also mobility and social security co-ordination where our positions are also driven far apart."

Barnier said he cannot understand why valuable time is being wasted in trying to secure a UK-EU trade deal.

"Too often this week it felt as if we were going backwards more than forwards," said Barnier.

"Given the short time left, what I said in London in July remains true. Today at this stage, an agreement between the UK and the European Union seems unlikely.

"I simply do not understand why we are wasting valuable time."

Barnier paid tribute to the late John Hume as he spoke of the importance of implementing the Protocol on Ireland and Northern Ireland.

He said: "Indeed, the proper implementation of the Protocol is the only way to preserve Ireland's whole-island economy, to protect the integrity of the single market, and above all, to ensure continued peace and stability on the island of Ireland.

"And in saying this, I want to pay tribute once again to the dedication and determination of John Hume who sadly left us a few weeks ago."