Prime Minister of the United Kingdom the incumbent is consistently ranked as one of the most powerful and influential people in the world. The Prime Minister is the head of the United Kingdom government. As such, the modern Prime Minister leads the Cabinet (the Executive). In addition, the Prime Minister leads a major political party and generally commands a majority in the House of Commons (the lower House of the legislature). The incumbent wields both significant legislative and executive powers. Under the British system, there is a unity of powers rather than separation. In the House of Commons, the Prime Minister guides the law-making process with
House of Commons of the United Kingdom a different one). By this second mechanism, the government of the United Kingdom can change without an intervening general election. Only four of the eight last Prime Ministers have attained office as the immediate result of a general election; the others have gained office upon the resignation of a Prime Minister of their own party. The latter four were Jim Callaghan, John Major, Gordon Brown and the current Prime Minister Theresa May; these four inherited the office from Harold Wilson, Margaret Thatcher, Tony Blair and David Cameron respectively. In such circumstances there may not even have been an internal party