UK threat over NI Brexit deal ‘breeding mistrust in EU capitals’

Anger and disbelief within EU at UK’s position given goodwill Boris Johnson has built up over Ukraine

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The British government’s plan to walk away from parts of the Northern Ireland Brexit deal is destroying the repaired relationship with the EU, political leaders and diplomats have said.

Leo Varadkar, Ireland’s deputy prime minister, told a business dinner in Dublin on Tuesday night that the move was “breeding mistrust in EU capitals”.

A measure of the anger and disbelief within the EU was reflected in a tweet posted by the German diplomat Sebastian Fischer, considered one of the most mild-mannered of his cadre in Brussels.

“Let’s just all threaten each other with breaking international law. Makes for really good partnerships #Brexit,” he tweeted on Tuesday evening.

“If you are wondering what friends and allies think …” tweeted Ireland’s foreign minister, Simon Coveney, in response.

There is a growing feeling of disbelief and disappointment in the EU over the UK’s position, given the goodwill Boris Johnson had built up over Ukraine.

“The fact that the UK government is talking openly about breaching international law is a matter of concern,” Varadkar said. “[It] stands in contrast with the enormous leadership the UK government is showing in supporting Ukraine against Russia, which has breached international law in a very serious way,” the tánaiste said.

He co-designed the protocol with Johnson in October 2019 to deliver a breakthrough that helped the Conservative party leader present what he described as an “oven-ready” real to the electorate in an election the following December.

Related: What is the Northern Ireland protocol and why is it back in the news?

There are fears that the relationship between London and Brussels, which had deteriorated badly over the past four or five years due to Brexit, has once again been damaged.

Diplomats have expressed incredulity at the British move, which threatens to splinter western unity against Vladimir Putin.

But one EU source said they had expected the move and believe Johnson will ultimately pull back from any attempt to break a treaty signed two years ago.

“There will be American pressure on Boris Johnson. The US will not want to see a rift in Europe at this time. It simply will not allow a trade war,” they said.

EU leaders have argued that there is scope to change the protocol but they had been waiting for the UK’s response to proposals in October and subsequent suggestions laid out in February.

Speaking in Dublin on Tuesday, Coveney said there had been “no serious engagement since February” between the EU and the UK, contrary to claims by the foreign secretary, Liz Truss in the Commons that she had been engaged in talks for the past six months.

“Instead of engaging, the British government has decided that it is going to threaten domestic legislation to set aside elements of the protocol which is part of an international treaty … I think that is going to cause a lot more problems than it solves if they go ahead and do that,” Coveney said.