Paris will ask the European Commission to open post-Brexit litigation proceedings against Britain over a long-running dispute on fishing licenses for French boats in British waters, France’s European affairs minister said Friday.

“In the coming days we will ask the European Commission to launch litigation, a legal procedure, for the licenses we are entitled to,” Clement Beaune said after President Emmanuel Macron met fishing representatives and local officials.

French fishermen say Britain and the Channel Island of Jersey, a British crown dependency, are holding back on licenses for French boats that had been allowed to ply their waters for years before Britain left the EU.

The dispute has sparked the possibility of an all-out trade war, with fishermen in northern France vowing this week to step up protests and block British boats from French ports along the Channel coast.

Britain agreed to issue an additional 23 licences to French fishermen on Saturday, but France believes it is entitled to around 80 more UK licences.

The European Union had set London a December 10 deadline to grant licences to dozens of French fishing boats under the post-Brexit trade accord signed last year, with Paris threatening European legal action if no breakthrough emerged.

READ MORE Why the new fishing row between France and UK could get nasty

Legal proceedings could see the EU impose financial penalties or even tariffs on British goods if Britain is judged to be reneging on its commitments.

The two countries have clashed repeatedly this year over fishing as well as migrants crossing the Channel, post-Brexit trade arrangements and the sale of submarines to Australia.

London briefly deployed two gunboats in May when dozens of French trawlers massed off the Channel Island of Jersey to protest the licensing problems, prompting France to send two coastal patrol vessels.

French President Emmanuel Macron last week accused UK Prime Minister Boris Johnson’s government of failing to keep its word on Brexit, saying “the problem with the British government is that it does not do what it says”.

The EU and Britain are also locked in a separate trade row over checks on products entering the British province of Northern Ireland after the UK government unilaterally postponed the introduction of checks.