Royal prerogative in the United Kingdom in the context of "British Government"

The prime minister of the United Kingdom is the head of government of the United Kingdom. The prime minister advises the sovereign on the exercise of much of the royal prerogative, chairs the Cabinet, and selects its ministers. Modern prime ministers hold office by virtue of their ability to command the confidence of the House of Commons, so they are invariably members of Parliament.

The office of prime minister is not established by any statute or constitutional document, but exists only by long-established convention, whereby the monarch appoints as prime minister the person most likely to command the confidence of the House of Commons. In practice, this is the leader of the political party that holds the largest number of seats in the Commons. The prime minister is ex officio also First Lord of the Treasury (an office often associated with the premiership between 1721 and 1895, after 1902 always united to it, and, after 1905, an official title of the position), Minister for the Civil Service, the minister responsible for national security, and Minister for the Union. The prime minister's official residence and office is 10 Downing Street in London.

His Majesty's Government, abbreviated to HM Government or otherwise UK Government, is the central executive authority of the United Kingdom of Great Britain and Northern Ireland. The government is led by the prime minister (Keir Starmer since 5 July 2024) who selects all the other ministers. The government is currently supported by the Labour party, which has had a majority in the House of Commons since 2024. The prime minister and his most senior ministers belong to the supreme decision-making committee, known as the Cabinet.

Ministers of the Crown are responsible to the House in which they sit; they make statements in that House and take questions from members of that House. For most senior ministers this is usually the elected House of Commons rather than the House of Lords. The government is dependent on Parliament to make primary legislation, and general elections are held at least once every five years to elect a new House of Commons, unless the prime minister advises the monarch to dissolve Parliament, in which case an election may be held sooner. After an election, the monarch selects as prime minister the leader of the party most likely to command the confidence of the House of Commons, usually by possessing a majority of MPs.

The Privy Council, formally His Majesty's Most Honourable Privy Council, is a formal body of advisers to the sovereign of the United Kingdom. Its members, known as privy counsellors, are mainly senior politicians who are current or former members of either the House of Commons or the House of Lords.

The Privy Council formally advises the sovereign on the exercise of the royal prerogative. The King-in-Council issues executive instruments known as Orders in Council. The Privy Council also holds the delegated authority to issue Orders of Council, mostly used to regulate certain public institutions. It advises the sovereign on the issuing of royal charters, which are used to grant special status to incorporated bodies, and city or borough status to local authorities. Otherwise, the Privy Council's powers have now been largely reserved to its executive committee, the Cabinet of the United Kingdom, which serves as the senior decision-making body of the government. The council is administratively headed by the Lord President of the Council who is a member of the cabinet, and appointed on the advice of the Prime Minister.

The United Kingdom has an uncodified constitution. The constitution consists of legislation, common law, Crown prerogative and constitutional conventions. Conventions may be written or unwritten. They are principles of behaviour which are not legally enforceable, but form part of the constitution by being enforced on a political, professional or personal level. Written conventions can be found in the Ministerial Code, Cabinet Manual, Guide to Judicial Conduct, Erskine May and even legislation. Unwritten conventions exist by virtue of long-practice or may be referenced in other documents such as the Lascelles Principles.