UK Prime Minister Boris Johnson has vowed to defend British interests in the deepening fishing row with France.
A UK government spokesperson said earlier in the day that Britain could launch dispute proceedings if France carries out its threat to issue London with a series of sanctions next week amid a simmering fishing row, which erupted after Britain's departure from the European Union.
"Lord Frost made clear that, if these actions were implemented as planned on 2 November, they would put the European Union in breach of the Trade and Cooperation Agreement (TCA)," the spokesman said after a meeting between Brexit minister David Frost and the European Commission's vice-president Maros Sefcovic.
The spokesman said that the British government "is accordingly considering the possibility, in those circumstances, of launching dispute settlement proceedings under the TCA, and of other practical responses."
Sefcovic earlier urged the UK to ramp up talks with the EU - and France, in particular - to put an end to the post-Brexit fishing rights debacle. Meanwhile, the European Commissioner for the Internal Market, Thierry Breton, has sided with France in the dispute, saying he "completely understand the position and the exasperation" of Paris.
"The support of the European Commission is there and it always has been from the start," Breton stated.
On Friday, UK Environment Secretary George Eustice pledged to retaliate if France goes through with its threats to block British fishing ships from French ports.
"We will see what they do. But if they do bring these [threats] into force, well... two can play at that game and we reserve the ability to respond in a proportionate way," he told Sky News.
The UK also decided to summon French Ambassador Catherine Colonna to the Foreign Office on Friday.
"We regret the confrontational language that has been consistently used by the French government on this issue, which makes this situation no easier to resolve," the British government said.
French authorities seized a British trawler at Le Havre on Wednesday, accusing it of scooping up more than two tonnes of scallops in French waters without a proper permit. On Friday, French prosecutors ordered a trial for the captain of the vessel. He faces a hearing next August on a charge of "non-authorised fishing in French waters", which carries a maximum fine of 75,000 euros and potential "administrative penalties". The UK is at present investigating the incident.
The second UK vessel caught in French waters on Friday was fined for non-compliance with orders of the maritime patrol team.
France, which has long accused the UK of refusing to issue fishing licences to dozens of its vessels, has warned that unless permits are given a green light, British boats will be barred from unloading their hauls at French ports from 2 November. London, which rejects France's accusations, has pledged to provide "an appropriate and calibrated response" to the measure taken by Paris.
In early October, French Prime Minister Jean Castex called on the European Commission to strictly monitor the UK's compliance with commitments under the agreement on fishing rights. He did not rule out that bilateral cooperation with London might be reviewed if it fails to adhere to the post-Brexit arrangements. Britain, in turn, insists that it sticks to the deal.
In late September, the British Ministry of the Environment reported that 1,700 vessels from the EU received licences to fish in UK waters, of which 117 were issued to vessels from the EU for fishing in a zone of 6-12 nautical miles. The ministry issued only 12 licences to French fishermen, having considered 47 applications.