 Prerogative powers were formerly exercised by the monarch acting on his or her own initiative . Since the 19th century , by convention , the advice of the prime minister or the cabinet — who are then accountable to Parliament for the decision — has been required in order for the prerogative to be exercised . The monarch remains constitutionally empowered to exercise the royal prerogative against the advice of the prime minister or the cabinet , but in practice would only do so in emergencies or where existing precedent does not adequately apply to the circumstances in question . 
 Prerogative powers <a href='uninflect' title='1'><mark>were</mark></a> formerly exercised by the monarch acting on his or her own initiative . Since the 19th century , by convention , the advice of the prime minister or the cabinet — <a href='null_relcl' title='2'><mark>who</mark></a><a href='drop_aux' title='3'><mark>are</mark></a>then accountable to Parliament for the decision — <a href='been_done' title='4'><mark>has</mark></a> been required in order for the prerogative to be exercised . The monarch <a href='uninflect' title='5'><mark>remains</mark></a> constitutionally empowered to exercise the royal prerogative against the advice of the prime minister or the cabinet , but in practice would only do so in emergencies or where existing precedent <a href='uninflect' title='6'><mark>does</mark></a> not adequately apply to <a href='None' title='7'><mark>the</mark></a><a href='negative_concord' title='8'><mark>circumstances</mark></a> in question . 
Prerogative powers was formerly exercised by da monarch acting on his or her own initiative . Since the 19th century , by convention , the advice of the prime minister or the cabinet — then accountable to Parliament for tdadecision — done been required in order fa the prerogative to be exercised . The monarch remain constitutionally empowered to exercise thdaoyal prerogative against thedavice of the dame minister or the cabinet , but in practice would only do soo in emergencies or where existing precedent do not adequately apply to no circumstances in question .