After Polish ruling, EU Commission to ensure primacy of EU law

European commission President Ursula von der Leyen address a media conference at the conclusion of EU- Western balkans summit in Brdo pri Kranju, Slovenia, October 6, 2021. /Handout via REUTERS

BRUSSELS (Reuters) - The European Commission will do all in its power to ensure the primacy of EU law, its president Ursula von der Leyen said on Friday, after a ruling by Poland's highest court that had left her "deeply concerned".

The Polish Constitutional Tribunal ruled on Thursday that some parts of EU treaties are incompatible with the Polish constitution, challenging a pillar of the European Union and sharply escalating discord between Brussels and Warsaw.