The European Commission said on Thursday it was suing Hungary over a law that imposes jail terms for groups that accept foreign funds for political causes.

The Commission opened an infringement procedure in February over the Hungarian law on "protecting national sovereignty," which it considers violates the union's democratic values and fundamental rights.

"After carefully assessing the reply of the Hungarian authorities, the Commission maintains that most of the grievances identified have still not been addressed," the Commission said in a statement.