BRUSSELS (AP) — It was late on Christmas Eve last year when the European Union and Britain finally clinched a Brexit trade deal after years of wrangling, threats and missed deadlines to seal their divorce.
There was hope that now-separated Britain and the 27-nation bloc would sail their relationship toward calmer waters.
Don't even think about it.
Such was the bile and bad blood stirred up by the diplomatic brinkmanship and bitter divorce that, two months from another Christmas, insults of treachery and duplicitousness are flying again.
“It was written in the stars from the start,” sighed Professor Hendrik Vos of Ghent University. "There were a lot of loose ends. Several issues that would invariably lead to problems, like fisheries and trade in Northern Ireland.”
It was the economically minute but symbolically charged subject of fish that held up a trade deal to the last minute. And fishing is also providing a wedge of division now.
This week France was rallying its EU partners for a joint stance and action if necessary if London wouldn't grant more licenses for small French fishing boats to roam close to the U.K. crown dependencies of Jersey and Guernsey that hug France's Normandy coast.
In France's parliament last week, Prime Minister Jean Castex accused Britain of reneging on its promise over fishing.
“We see in the clearest way possible that Great Britain does not respect its own signature,” he said, adding that “all we want is that a given word is respected.”
In a relationship where both sides often fall back on cliches about the other, Castex was harking back to the centuries-old French insult of “Perfidious Albion,” a nation that can never be trusted.
His Europe Minister Clement Beaune added to this late Monday. “The European Union scrupulously implements the agreement it reached with the United Kingdom. We expect the same from Britain."
Across the English Channel, Brexit supporters in British politics and the media often depict a conniving EU, deeply hurt by the U.K.'s decision to leave, and doing its utmost to make Brexit less than a success by throwing up bureaucratic impediments.
The schism has crystalized in the worsening fight over Northern Ireland, the only part of the U.K. to share a land border with an EU country. Under the most delicate and contentious part of the Brexit deal, Northern Ireland remains inside the EU's single market for trade in goods, in order to avoid a hard border with EU member Ireland.
That means customs and border checks must be conducted on some goods going to Northern Ireland from the rest of the U.K., despite the fact they are part of the same country.
The regulations are intended to prevent goods from Britain entering the EU’s tariff-free single market while keeping an open border on the island of Ireland — a key pillar of Northern Ireland’s peace process.
The U.K. government soon complained the arrangements weren't working. It said the rules and restrictions impose burdensome red tape on businesses. Never short of a belligerent metaphor, 2021 has already brought a “sausage war,” with Britain asking the EU to drop a ban on processed British meat products such as sausages entering Northern Ireland.
Northern Ireland's British Unionist community, meanwhile, say the Brexit deal undermines the peace process by weakening Northern Ireland’s ties with the rest of the U.K.
Britain accuses the EU of being needlessly “purist” in implementing the agreement, known as the Northern Ireland Protocol, and says it requires major changes to work.
The bloc has agreed to look at changes, and is due to present proposals on Wednesday. Before that move, Britain raised the stakes again, demanding even more sweeping changes to the jointly negotiated deal.
In a speech in the Portuguese capital, Lisbon, on Tuesday, U.K. Brexit minister David Frost will say the EU must also remove the European Court of Justice as the ultimate arbiter of disputes concerning trade in Northern Ireland.
That is a demand the EU is highly unlikely to agree to. The bloc's highest court is seen as the pinnacle of the free trade single market, and Brussels has vowed not to undermine its own order.
“No one should be in any doubt about the seriousness of the situation,” Frost will say in Lisbon, urging the EU to "show ambition and willingness to tackle the fundamental issues at the heart of the Protocol head on.”
Frost plans to say that if there is no resolution soon, the U.K. will invoke a clause that lets either side suspend the agreement in exceptional circumstances.
That would send already testy relations into a deep chill and could lead to a trade war between Britain and the bloc — one that would hurt the U.K. economy more than its much larger neighbor.
Some EU observers say Britain's demand to remove the court's oversight shows it isn't serious about making the Brexit deal work.
Irish Foreign Minister Simon Coveney accused Britain of “shifting the playing field” and dismissing EU proposals without seeing them.
“This is being seen across the European Union as the same pattern over and over again — the EU tries to solve problems, the U.K. dismisses the solutions before they’re even published and asks for more,” Coveney said.
Jill Lawless reported from London.
Follow AP's coverage of post-Brexit developments at https://apnews.com/hub/Brexit