LONDON (AP) — French authorities fined two British fishing vessels and kept one in port overnight Thursday amid a worsening dispute over fishing licenses that has stoked tensions following the U.K.'s departure from the European Union.

Britain's government warned France that it would it retaliate if French officials followed through on threats made late Wednesday to block British boats from some French ports and tighten checks on U.K. vessels. France also suggested it might restrict energy supplies to the Channel Islands, British Crown dependencies that lie off the coast of France.

“We believe these are disappointing and disproportionate, and not what we’d expect from a close ally and partner,″ U.K. Environment Secretary George Eustice told lawmakers. “The measures being threatened do not appear to be compatible with the trade and cooperation agreement or wider international law, and if carried through will be met with an appropriate and calibrated response.”

Since the U.K. left the economic orbit of the EU at the start of the year, relations between London and Paris have become increasingly frayed as the nations on either side of the English Channel sought to sort out a post-Brexit path.

France vehemently protested the decision last month by the U.K. and the Channel Island of Jersey to refuse dozens of French fishing boats licenses to operate in their territorial waters. France says the restrictions are contrary to the post-Brexit agreement that the British government signed when it left the EU.

After weeks of negotiations, British authorities have issued more fishing licenses, but the number still only accounts for 50% of what France believes it “is entitled to,” French government spokesman Gabriel Attal said Wednesday.

“We have worked with the British, we gave them all the requested data, documents, information to back these (license) requests,” Attal said. “Our patience has reached its limits today.”

Britain disputes that. The government says it has granted 98% of fishing license applications from European vessels, but there is a dispute over 31 vessels which the U.K. says did not supply evidence to support their applications.

It was against this backdrop that French authorities fined the two British boats, one for failing to comply with checks by police and the other for not holding a proper license.

The French Sea Ministry said in a statement that the fines resulted from bolstered boating and license checks that are “part of the tightening of controls in the Channel, in the context of discussions on licenses with the United Kingdom and the European Commission.”

“We have been extremely patient...Our fishermen have been extremely responsible," France’s Europe minister, Clement Beaune, told French TV news channel CNews. “And so, from November 2, it’s over. We will engage in dialogue if the British want to, but we are taking retaliatory measures.”

As part of the retaliatory measures, France “doesn’t exclude” actions that would target energy supplies to Britain, Beaune and French Minister of the Sea Annick Girardin said in a joint statement. Government spokesman Attal specified that the threat applied to the Channel Islands, which are closer to French shores than British ones and rely heavily on electricity supplied by the French grid.

Jersey, which is only 14 miles (22 kilometers) off the French coast, is a British Crown dependency outside of the U.K. As such, it has its own powers over who is allowed to fish in its territorial waters. It has granted licenses based on its interpretation of the U.K.-EU trade deal, and has accused France of acting disproportionately.

Barrie Deas, from the U.K.'s National Federation of Fishermen’s Organizations said the “tit-for-tat” actions are “unhelpful.″

“It may be normal enforcement action, but against the background of the threatening noises coming from the French government, it’s very concerning,″ Deas told the BBC. “France seems determined to escalate this issue about licenses, and I suppose we have to wonder why.”


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