Powers of the prime minister of the United Kingdom

The powers of the prime minister of the United Kingdom come from several sources of the UK constitution, including both statute and constitutional convention, but not one single authoritative document. They have been described as "...problematic to outline definitively."^[1]: p.4

The UK has a fusion of powers, which means that the prime minister exercises functions in both the executive and the legislature. This also means that accountability between the branches is limited, as it is difficult to check on oneself. The prime minister normally (but not necessarily) leads the largest party in the House of Commons and they usually have some power over their own party due to that role.

The status and executive powers of the British prime minister means that the incumbent is consistently ranked as one of the most powerful democratically elected leaders in the world.^{[citation needed]}