Post-Brexit trade talks between the UK and EU are approaching deadlock, with progress “frozen” as both sides refuse to back down on the key issues of fisheries and state aid.

EU negotiator Michel Barnier warned agreeing a deal before the deadline currently “seems unlikely”, as he suggested Britain is “wasting valuable time”.

His UK counterpart David Frost also warned “there has been little progress” after the conclusion of the seventh round of talks on Friday.

Both sides accept time is running out to broker a deal before the transition period comes to a close at the end of the year, which would see UK firms facing high tariffs for trade.

Mr Frost said he believes an agreement can still be struck, but he accused the EU of ruling out “any further substantive work” unless the UK accepts the bloc’s state aid rules and fisheries policy.

“This makes it unnecessarily difficult to make progress,” Mr Frost said, despite his team having offered a draft agreement in an attempt to unblock negotiations.

A senior negotiating official for the UK insisted “it’s not us that’s slowing it down”, and ruled out accepting Mr Barnier’s position: “Obviously we’re not going to do that. So it’s frozen.”

After a breakfast meeting between the top negotiators at the close of the talks in Brussels, Mr Barnier was equally as pessimistic about progress.

“Too often this week it felt as if we were going backwards more than forwards,” he told a press conference.

“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.”

He said “we have made no progress whatsoever” on the key issues of fishing policy, and said they “still struggle to agree on the necessary guarantees to protect citizens’ fundamental rights” in law enforcement.

He also reiterated the EU’s committance to the level playing field to prevent businesses on one side undercutting their rivals on the other with lower workers’ rights or environmental protections.

Mr Frost said they will “continue to work hard to reach an agreement”, with the next round of talks starting in London in the week of September 7.

Shadow chancellor of the Duchy of Lancaster Rachel Reeves urged Boris Johnson to “get a grip” and “rapidly accelerate talks” when he returns from his holiday in Scotland, with the disruption of a disorderly exit threatening to compound the economic fallout of coronavirus.

“Last December the Prime Minister told the country he had an ‘oven ready’ deal and in June he claimed it could be delivered by the end of July,” the Labour MP said.

“The failure to make more progress in August only adds to the uncertainty for industries from freight to farming.”

The two sides are currently in a transition period where the UK follows the EU’s rules and has access to the single market, but this ends on December 31.

Both parties have said any deal needs to be concluded by October in order to be ratified.