Traktatændringer, der er vedtaget i enighed af repræsentanter for medlemsstaternes regeringer, træder først i kraft efter at være blevet ratificeret af alle medlemsstaterne i overensstemmelse med deres forfatningsmæssige bestemmelser.
Treaty amendments agreed jointly by the representatives of the governments of the Member States only enter into force after being ratified by all the Member States in accordance with their respective constitutional requirements.