Prime Minister of Australia prime minister, otherwise William McMahon63. Robert Menzies was the oldest person to ever be prime minister, leaving office at 71 years old. The longest-serving Prime Minister was Sir Robert Menzies, who served in office twice: from 26 April 1939 to 28 August 1941, and again from 19 December 1949 to 26 January 1966. In total Robert Menzies spent 18 years, 5 months and 12 days in office. He served under the United Australia Party and the Liberal Party respectively. The shortest-serving Prime Minister was Frank Forde, who was appointed to the position on 6 July 1945 after the death of
Deputy Prime Minister of Yugoslavia and Jaša Prodanović. From then on, the office was usually held simultaneously by several people at the same time. Also, Deputy Prime Ministers sometimes combined the post with another government portfolio. The office of the Deputy Prime Minister of FR Yugoslavia was abolished with the constitutional reforms of 2003. Therefore, the last Deputy Prime Minister was Miroljub Labus, who served from 4 November 2000 to 17 March 2003. Deputy Prime Minister of Yugoslavia The Deputy Prime Minister of Yugoslavia was the official Deputy of the Prime Minister of the Kingdom of Yugoslavia, SFR Yugoslavia and later Prime Minister of FR