Britain on Friday blamed the European Union for holding up progress to secure a post-Brexit trade deal, as the seventh round of negotiations broke up.

Chief negotiator David Frost said Brussels' insistence that London accept EU state aid and fisheries policy before work on other areas made it "unnecessarily difficult to make progress".

Britain left the EU in January, nearly four years after a landmark referendum to end almost 50 years of European integration.

But it remains bound by EU rules until the end of this year as both sides try to thrash out the terms of their future relationship.

Frost reiterated that he thought a deal remained possible and was Britain's aim but he warned: "It is clear that it will not be easy to achieve."

The latest talks were "useful but there has been little progress", he added, highlighting continual sticking points on competition rules and fishing rights.

"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."

Time is running out for both sides to reach agreement, given the need for the deal and legal texts to be scrutinised by member states and ratified by the European parliament.

The next round of talks is scheduled to be held in London in the week of September 7, with UK officials eyeing the planned October 15-16 EU summit as the deadline for a deal.

AFP