Her Majesty's Government (HMG or HM Government), or when the monarch is male, His Majesty's Government, is the formal title used by the United Kingdom government, based at 10 Downing Street in London. The title is used because in the UK, executive authority is theoretically vested in the monarch and exercised through his or her ministers. In effect, the government is an executive authority consisting of the Sovereign's ministers. In Commonwealth usage, the term government does not relate to Parliament or the Courts but only to the executive branch.
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