In the dispute over customs regulations for Northern Ireland, the EU Commission launched four new infringement procedures against Great Britain on Friday.
Despite numerous appeals from the 27 EU countries to London to implement the Northern Ireland Protocol, the British government has refused, the Commission said in a statement.
For more than a year, attempts had been made to find common solutions in the spirit of constructive cooperation.
However, the UK is not ready to engage in serious talks on the issue.
Instead, unilateral changes to the protocol will continue to be debated in the British Parliament.
The proceedings brought by the EU could end up in London before the European Court of Justice.
The Northern Ireland Protocol is part of the Brexit agreement between Brussels and London and is intended to regulate customs controls in the exchange of goods between Northern Ireland and Great Britain.
London had originally agreed to the regulation to prevent controls at the inner-Irish border, as this could endanger the peace process in the former troubled region.
Now, however, the British government wants to abolish most controls between Northern Ireland and Great Britain and exempt British traders for goods to Northern Ireland from the obligation to make EU customs declarations.
London argues that the Northern Ireland Protocol undermines peace in the region by blocking government there.
The pro-British DUP party has been opposing the formation of a government in Northern Ireland for weeks and is calling for the Protocol to be abolished.
The EU rejects a fundamental revision of the agreement.
However, it has allowed practical simplifications in the controls.