The scope of the royal prerogative is difficult to determine due to the
uncodified nature of the
constitution. It is clear that the existence and extent of the power is a matter of the
common law of England, making the courts the final arbiter of whether a particular type of prerogative exists or not. Nevertheless, certain prerogative powers have been widely acknowledged and accepted over time, while others have fallen out of use.
The power to dissolve parliament is "perhaps the most important residual prerogative exercised personally by the sovereign, and represents the greatest potential for controversy."
The monarch could force the dissolution of Parliament through a refusal of royal assent;
The appointment of the prime minister is also, theoretically, governed by the royal prerogative. Technically the monarch may appoint as prime minister anyone he wants to appoint
The most noted prerogative power that affects the judicial system is the prerogative of mercy, which has two elements: the granting of pardons and the granting of nolle prosequi.
The royal prerogative is in much use in the realm of foreign affairs. It is the monarch who recognises foreign states, issues declarations of war and peace, and forms international treaties.
Monarchs also have power to exercise their prerogative over the granting of
honours, the regulation of the armed forces and ecclesiastical appointments.
The monarch also exerts a certain influence power on his or her weekly and closed conversations with the Prime Minister of the United Kingdom.