The UK government has renewed its attempt to reopen the chapter of the Brexit divorce treaty protecting specialty food and drink, such as Parma ham, roquefort cheese and champagne, in a move that left the EU chief negotiator, Michel Barnier, "a little bit flabbergasted".

The British proposal on protected status for food and drink was included in a draft free-trade agreement handed to Barnier by his opposite number, David Frost, last week, according to two EU sources.

But EU officials have ruled out diluting the divorce deal provisions that protect more than 3,000 high-end food and drink products from copycats. "It's just not going to happen," said one official.