However, Greg Hands, the Trade Minister, said Mr Barnier's "apparent change of heart" was "a question for him" and emphasised that the government's "mission" is to agree a Canada-style agreement with the EU.

Speaking to Sky News, he said: "If you look back right to the very beginning, what the EU was offering the UK was a Canada-style deal.

"In fact, one of the slides that Michel Barnier presented to European Council members some two or three years ago included precisely a Canada-style deal. So that is what the government, our government, is looking to get.

"Obviously there will be a bit of posturing from Brussels, as there always is. But our mission is clear."

On Wednesday night the British government also highlighted comments made by EU trade commissioner Phil Hogan, who said the level playing field commitments in Brussels' agreement with Canada are enough to protect the bloc’s interests.

Mr Hogan said the Canada agreement's "rules on environment and labour are solid and anchored in a vast network of underlying international conventions and agreements".

The EU's Canada deal has far less stringent "level playing field" guarantees in areas such as state aid and the environment than those demanded by Brussels from the UK.

Mr Hogan's remarks were made in a letter last week to the Dutch government, which is in the process of ratifying the EU's trade deal with Canada (CETA).

A UK source close to the negotiations said: "Given that the EU is praising the level playing field commitments in CETA in this way, it's surprising that they've suggested they would not be willing to accept similar provisions in a trade deal with the UK.

"It is worth noting that there is no reference to the ECJ in CETA, and no commitment to dynamic alignment on regulation. In its current form, the EU mandate asks the UK to commit to aligning with the EU’s standards forever."

Downing Street has pointed out that Britain even exceeds the EU in terms of standards in a number of areas.

In a speech on Monday in Brussels, Boris Johnson's chief EU negotiator, David Frost, explicitly ruled out Britain accepting any more draconian level playing field guarantees than those in other EU trade deals with countries such as Canada and Japan.

However the EU says the UK agreed to level playing field guarantees in the trade deal in the joint political declaration that sets the parameters of the trade talks.

Meanwhile, Mr Barnier's aide Stefaan De Rynck said: "Dover is closer to Calais than Ottawa" as he appeared to dismiss the UK's calls for a Canada-style trade deal.

Speaking at the London School of Economics, Mr De Rynck said the EU's trade agreement with Canada was a "different ball game".

Asked about the slide tweeted by Downing Street, he said: "There is a mild irony that some in the UK now seem to want to become Canadians... But of course Dover is much closer to Calais than Ottawa is. Distance matters and proximity matters in trade."

EU ambassadors met in Brussels on Wednesday night for further talks on the EU's draft mandate for the trade negotiations with Britain. The mandate must be finalised by February 25 so trade talks can begin next month.

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