THE UK Government has told France “two can play at that game” in a warning that there could be retaliation if Paris goes ahead with “inflammatory” threats made in a post-Brexit row over fishing rights.

Foreign Secretary Liz Truss will challenge Paris’s ambassador to the UK Catherine Colonna on France’s intentions later on Friday afternoon after taking the rare step of ordering an allied nation’s envoy to be summoned.

A Scottish trawler has been detained in a French port in an escalation of a diplomatic row triggered by France claiming there is a lack of licences for French boats to fish in UK waters.

French ministers have warned they will block British boats from some French ports and tighten checks on vessels travelling between France and the UK if the issue is not resolved by Tuesday – as well as threatening the electricity supply to the Channel Islands.

READ MORE: France detains Scottish trawler amid ongoing post-Brexit fishing row

Environment Secretary George Eustice did not rule out blocking French vessels in return as he struck out at a claim from France’s Europe minister Clement Beaune that the only language Britain understands is “the language of force”.

Eustice told BBC Breakfast: “That is completely inflammatory and is the wrong way to go about things.”

Asked how the UK will respond if France does go ahead and block British trawlers, the Cabinet minister said: “Two can play at that game.”

He insisted any British response would be “proportionate”, adding: “It’s always open to us to increase the enforcement we do on French vessels, to board more of them if that’s what they’re doing to our vessels – there are other administrative things we can require of vessels.”

Pressed if the Government could block French vessels landing their catches in the UK, he responded: “If the French obviously do continue with this, then yes, we will take a proportionate response to that.”

Eustice acknowledged that the France detaining the British vessel may have been a “routine operation” but has received mainstream attention because French authorities last week “said they were going to introduce all sorts of problems and make life difficult for people”.

Britain has said France’s threat would likely breach EU law and Ms Truss has said she will ask the ambassador “to explain the disappointing and disproportionate threats made against the UK and Channel Islands”.

UK ministers met on Thursday to consider the response, with the prospect of tit-for-tat action if France carries out its threats.

Brexit minister Lord Frost, who chaired the meeting, said: “I remain concerned by French plans on fisheries and beyond”, adding that “we expect to have more to say” on Friday.

The Government views the proposed actions as “unjustified” and questioned whether they were compatible with the UK-EU trade deal “or wider international law”.

READ MORE: Brexit's impact on economy worse than Covid pandemic's, warns OBR chief

A UK Government spokesman added: “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 scallop vessel Cornelis Gert Jan was caught up in the diplomatic storm, and ordered to divert to the port of Le Havre on Wednesday after the French authorities said it was fishing in French waters without a licence.

French officials said that another British trawler had also been fined for obstruction after refusing to allow police to board to carry out checks.

The owner of the Cornelis, Macduff Shellfish, said the vessel had been fishing legally in French waters and called on the British Government to protect the rights of British fishermen.

Andrew Brown, director of sustainability and public affairs at Macduff, said: “It appears our vessel has been caught up in the ongoing dispute between the UK and France on the implementation of the Brexit fishing agreement.”

On Thursday, Eustice told MPs the vessel had been granted a licence by the EU but that there were reports that it subsequently had been removed from the list of vessels permitted to fish in French waters for reasons that were unclear.

Earlier, Beaune told French TV news channel CNews: “We need to speak the language of force because, unfortunately, that seems to be the only thing this British Government understands.”

READ MORE: The one quote Brexit minister Lord Frost wants you to forget

French maritime minister Annick Girardin also told French radio news programme RTL Matin that Britain’s “failure to comply” with the UK-EU Trade and Co-operation Agreement (TCA) is “unacceptable”.

“It’s not war, it’s a fight,” she said.

“We have fishing rights, we must defend them and we will defend them.”

At the centre of the dispute are the licences for small boats, which are issued only if the vessels can demonstrate a history of fishing in British waters.

Eustice told MPs on Thursday that 171 vessels have been licensed to fish in the UK six to 12 nautical mile zone, of which 103 are French, and 18 of those vessels are under 12 metres.