The European Commission carried out its threat on Thursday over launching legal action against the UK government regarding its law-breaking Internal Market Bill.
A letter of formal notice has been sent to the UK government.
The British government has previously publicly admitted the bill breaks international law by unilaterally overriding key parts of the Withdrawal Agreement the UK signed with the EU.
European Commission President Ursula von der Leyen said the bill was a breach of the “good faith” provisions in the Withdrawal Agreement, and was “in full contradiction” to the Northern Ireland Protocol.
“We had invited our British friends to remove the problematic parts of their draft Internal Market Bill by the end of September," von der Leyen said. "The deadline lapsed yesterday. The problematic provisions have not been removed, therefore this morning, the Commission has decided to send a letter of formal notice to the UK government. This is the first step in an infringement procedure.”
“Besides this the Commission will continue to work hard towards a full and timely implementation of the Withdrawal Agreement. We stand by our commitments,” she said.
Brussels had previously given London time until the end of September to remove the offending clauses of the bill.
Northern Ireland Secretary Brandon Lewis said in parliament last month that the bill “does break international law in a very specific and limited way.”
The Withdrawal Agreement has the legal force of an international treaty, and as such cannot be unilaterally changed, the EU said.
The EU will continue negotiating with the UK, as it does not want to be blamed for the potential failure of Brexit talks.