The European Union said Saturday it was weighing its “next steps” after Britain formally responded to Brussels over the launch of legal proceedings alleging London broke the Brexit protocol covering Northern Ireland. “We can confirm that the United Kingdom replied on 14 May to the European Commission’s letter of formal notice, sent on 15 March,” a European Commission spokesperson said. “The Commission will now assess the contents of the letter before deciding on next steps.” The EU began an “infringement procedure” in March after London unilaterally delayed until October the introduction of custom controls on goods arriving in Northern Ireland from mainland Britain. Brussels says this violates the protocol of the 2019 divorce pact that deals with Ireland, one of the most sensitive and fought over issues of Britain’s break from bloc membership after 47 years. The two sides insist they are working hard to find a solution after the protocol helped generate a leadership crisis and unrest in Northern Ireland. The protocol is designed to prevent the emergence of a “hard border” between Northern Ireland, which remains part of the United Kingdom, and its EU neighbour, the Republic of Ireland.