LONDON — The European Union on Thursday launched legal action against the United Kingdom over London's plan to unilaterally breach a Brexit withdrawal agreement both sides signed last year.
In the latest setback to Britain's attempt to separate itself from the E.U., the European Commission said in a statement that the country had been put on "formal notice" for tabling its own law that by British ministers' admission breaches international law.
The statement said the U.K.'s controversial Internal Market Bill would "flagrantly violate" the rules governing the border between the Irish Republic and Northern Ireland — a key stumbling block in Brexit talks for the last four years.
European Commission President Ursula von der Leyen said in a separate statement that the U.K.'s plan "by its very nature is a breach of the obligation of good faith laid down in the Withdrawal Agreement."
"We stand by our commitments," she added.
The U.K. has already left the E.U. but has the same rules and standards thanks to a transition agreement that expires at the end of 2020. Both sides have spent this year trying to agree on a free trade deal that will allow the movement of goods to and from Britain.
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Frustrated with a lack of progress on several key issues, Prime Minister Boris Johnson introduced his own domestic legislation to solve the Irish border question earlier this month — to the outrage of European diplomats.
European Commission Vice President Maroš Šefčovič has said that if the bill was passed, it would "constitute an extremely serious violation of the Withdrawal Agreement and of international law."
The U.K. has one month to respond to Thursday's letter or it will face further steps, potentially including court action.