Earlier this week, Boris Johnson denied the UK had offered any concessions on fishing to Paris after Emmanuel Macron backed down on his threats to impose sanctions.

Jean-Baptiste Djebbari, the French transport minister, argued that the “balance of power” in the row was in France’s favour, telling Europe 1 radio: “The British have a lot more to lose by not implementing the Brexit agreement between the EU and  the UK than the reverse.”

Mr Djebbari also said British officials were negotiating in “good faith”, adding: “The spirit is a constructive one on this topic.”

In another sign Paris was softening its position, a French government spokesman suggested planned sanctions would be delayed until Friday.

Gabriel Attal, a close ally of Mr Macron, said the French government would not move before a meeting with the European Commission on that day, when Lord Frost is also set to meet Maros Sefcovic, a European Commission vice-president, in Brussels. European officials are privately confident that a deal to end the 10-month dispute can be struck.

“Officials from the UK, France, Jersey and the Commission have been meeting for the past two days. These talks have allowed us to chart the way forward on several aspects and have created a positive dynamic aiming at a solution,” a commission spokesman said. “We hope the positive engagement on all sides will soon translate into concrete results.”