PARIS (Reuters) – French lawmakers have urged the government to stay firm over fishing in Brexit negotiations, potentially complicating EU negotiator Michel Barnier’s ability to compromise with Britain.

In a report approved by the National Assembly’s European affairs committee on Thursday, lawmakers urged President Emmanuel Macron’s government to keep French fishermen’s right to fish in British waters.

“The Union must continue to guarantee that fishing won’t be sacrificed to save other sectors,” the report seen by Reuters says. The report was co-written by Jean-Pierre Pont, a member of parliament for Macron’s party who represents the town of Boulogne on the English Channel, France’s busiest fishing port.

Britain’s government has said it want to have full control over its waters and fish in its future outside the European Union.

EU diplomats had told Reuters last month the EU was willing to shift its stance on fisheries and move from the “maximalist position” of maintaining the situation as it is in order to help forge a trade deal with Britain.

Lawmakers also urged Paris to do more to prepare for a no-deal, which they said was the “most likely scenario”.

British fishing grounds are among the richest in the North East Atlantic zone where most of the EU catch is hauled in.