 Today , some prerogative powers are directly exercised by ministers without the approval of Parliament , including the powers of declaring war and of making peace , the issue of passports , and the granting of honours . Prerogative powers are exercised nominally by the monarch , but on the advice of the prime minister ( whom the monarch meets weekly ) and of the cabinet . Some key functions of the British government are still executed by virtue of the royal prerogative , but generally the usage of the prerogative has been diminishing as functions are progressively put on a statutory basis . 
