France had repeatedly refused to apply a 2002 EU law that set out rules by which biotech crops could be planted in areas where other conventional crops were grown. France argued it could not adopt the rules because of violent anti-GMO demonstrations. The EU court rejected those arguments. France has applied the law since July.

The Luxembourg-based court says France's conduct was "unlawful" and said Tuesday's ruling should act as a warning to others that ignoring EU regulations has a price.