UK post-Brexit trade rule rewrite spurs suit

BRUSSELS — The European Union sued Britain on Wednesday over its move to rewrite the trade rules agreed to when the country left the EU two years ago, ratcheting up tensions between the major economic partners.

This week, British Prime Minister Boris Johnson’s government proposed legislation that would remove customs checks on some goods entering Northern Ireland from the rest of the U.K. Those checks were imposed as part of a hard-fought compromise when Britain left the EU and its borderless free-trade zone — but have caused both economic and political problems in Northern Ireland, where some say they undermine the region’s place in the United Kingdom.

The EU’s decision to pursue legal action raises the possibility that one or both sides could impose punishing tariffs on the other. But the prospect of trade war still seemed a distant possibility since both would suffer and have said they want to find a solution outside of the courts.

According to the latest EU figures, the 27-nation bloc is the U.K.’s biggest trading partner, while the U.K. is the EU’s third-biggest partner after the U.S. and China.

At the heart of the dispute — and the whole reason a compromise was needed in the first place — are concerns about stability in Northern Ireland, which is the only part of the U.K. that shares a border with an EU country, namely Ireland. The checks were imposed in order to keep that border open because that is a key pillar of the peace process that ended decades of violence in Northern Ireland.

But British unionists in Northern Ireland say the new checks have put a burden on businesses and frayed the bonds between the region and the rest of the U.K. The rules have also led to a political crisis in Northern Ireland, where the main unionist party blocked the formation of a new power-sharing government in Belfast, saying it won’t take part until the Brexit trade rules are scrapped.

The British government called the EU’s move “disappointing.”