Prime Minister of New Zealand ministerial power; in 1912 Thomas Mackenzie was the last prime minister to lose power through an unsuccessful confidence motion in the House of Representatives. One change brought about by the First World War was direct participation in governing the British Empire. Previously, New Zealand prime ministers had attended occasional colonial and imperial conferences, but they otherwise communicated with London through the governor (a position then appointed by the British government). In 1917, however, British Prime Minister David Lloyd George offered the New Zealand prime minister a seat in the Imperial War Cabinet, the British Empire's wartime coordinating body. In 1919,
Prime Minister of New Zealand signed a number of international treaties. In 1967, Keith Holyoake became the first New Zealand prime minister to select candidates for the position of governor-general without any involvement of the British government. Holyoake advised the monarch, Queen Elizabeth II, to appoint Sir Arthur Porritt, the first New Zealand–born governor-general. After the mixed-member proportional (MMP) system was introduced in 1996, prime ministers have had to manage minority governments. The skill of MMP management was exemplified by Helen Clark's nine years as prime minister (1999–2008), when her Labour Party remained in power thanks to a range of confidence and supply agreements with