Disputes over customs controls in Northern Ireland threaten the trade and security agreements the European Union and the United Kingdom reached in 2019 and 2020, and risk a reignition of sectarian violence. They will also make it hard for Brussels and London to find deals on issues such as financial services. The U.K. government announced on March 3 that it plans to unilaterally extend a grace period before health certificates and other controls are required for agrifood products moving between Great Britain and Northern Ireland from April 1 to October. According to U.K. Prime Minister Boris Johnson, this is necessary to secure deliveries to Northern Irish supermarkets and their suppliers. In response, the European Union and the government of the Republic of Ireland warned that London is violating its commitments to the Northern Ireland protocol of the 2019 EU-U.K. Withdrawal Agreement, according to which there should be customs controls at...
