The British government described France's call for harsher EU action against the United Kingdom over fishing rights as extremely disturbing and quite problematic, POLITICO reported.
In a letter delivered on Thursday, French Prime Minister Jean-Claude Juncker warned that the United Kingdom's refusal to comply with French demands on fishing permits would harm the EU as a whole. Castex warned European Commission President Ursula von der Leyen that it must show that leaving the EU is more detrimental than remaining in it.
As the row clouded G20 leaders' discussions in Rome, Brexit Minister David Frost retaliated in a lengthy Twitter thread.
He expressed his hope that France's viewpoint was "not shared more widely across the EU," because "to see it stated in this way is plainly unsettling and troublesome."
"Unfortunately, part of a pattern that has persisted for much of this year," Frost said of France's "threats."
According to Frost, the United Kingdom is now seriously considering taking legal action under the Trade and Cooperation Agreement, echoing what he informed his EU counterpart over lunch on Friday.
The latest flare-up in Franco-British tensions occurred as Boris Johnson met with counterparts, including von der Leyen, as part of his efforts to create momentum ahead of the COP26 meeting in Glasgow, which the UK is hosting next week.
The prime minister "stressed that the French threats are completely unjustified and do not appear to be compatible with the UK-EU Trade and Cooperation Agreement or wider international law," according to a Downing Street spokesperson who confirmed Johnson had raised concerns with the Commission president.
Even while the British prime minister has stated they are "old friends," it will make for an unpleasant backdrop when Johnson and Emmanuel Macron talk at a so-called brush-by in Rome on Sunday.