Parliamentary primacy over conflicting state laws ensures central enactments prevail, rendering inconsistent state provisions inoperative while in force. States retain their constitutional legislative competence despite Parliament's powers under arts. 249 and 250. If a State provision is repugnant to a law enacted by Parliament under those articles, the parliamentary law prevails whether enacted before or after, and the inconsistent part of the State law is inoperative to the extent of the repugnancy while the parliamentary law continues to have effect.