The French government has voiced anger over what it calls new UK fishing rules in the Channel and warns it could cut electricity to Jersey in response.
Maritime Minister Annick Girardin told the French parliament that the new rules governing access to Channel Islands waters were unacceptable.
She said “we are ready to use the retaliatory measures” under the UK-EU post-Brexit trade deal.
She then mentioned France’s underwater cables supplying power to Jersey.
“I am sorry it has come to this [but] we will do so if we have to,” she said.
In a statement to AFP news agency, the French fisheries ministry said the UK had introduced “new technical measures” linked to licences for fishing off the Channel Islands, which had not been communicated to the EU and were, therefore, “null and void”.
The UK’s exit from the EU means it is no longer part of the European Common Fisheries Policy, and fishing rules were among the toughest issues in the Brexit negotiations.
A week ago French Europe Minister Clément Beaune accused the UK of blocking fishing rights. He said the EU could respond with “reprisals” in financial services.
French fishermen have complained of being prevented from operating in British waters because of difficulties in obtaining licences.
Meanwhile, British seafood exporters have been hit by an EU ban on UK exports of live shellfish. Scottish firms account for most of that business, and some now face collapse.
Last week the UK also failed to get a new fishing agreement with Norway. That failure threatens to prevent British trawlers catching cod in Norway’s sub-Arctic seas.