the essentials of the office were the same. Modern usage In the late 20th century, many of the world's countries had prime ministers or equivalent ministers, holding office under either constitutional monarchies or ceremonial presidents. The main exceptions to this system include Switzerland and the United States, as well as the presidential republics in Latin America, such as Chile and Mexico, modelled on the U.S. system in which the president directly exercises executive authority. Bahrain's former prime minister, Sheikh Khalifah bin Sulman Al Khalifah, occupied the post for about 50 years, from 1970 to November 2020, making him the longest serving non-elected prime minister. Overview of the office In monarchies and in republics The post of prime minister may be encountered both in constitutional monarchies (such as Belgium, Denmark, Japan, Luxembourg, the Netherlands, Norway, Malaysia, Morocco, Spain, Sweden, Thailand, Canada, Australia, New Zealand, and the United Kingdom) and in parliamentary republics, in which the head of state is an elected official (such as Bangladesh, Finland, the Czech Republic, France, Greece, Hungary, India, Indonesia (1945–66), Ireland, Nigeria (1960–66), Pakistan, Portugal, Montenegro, Croatia, Bulgaria, Romania, Serbia, Turkey (1923–2018) and Italy). See also "First Minister", "Premier", "Chief Minister", "Chancellor", "Taoiseach", "Minister of State (Statsminister)", "President of the Government", "President of the Council of Ministers" and "Secretary of State": alternative titles usually equivalent in meaning to, or translated as, "prime minister". Both Indonesia and Nigeria lost their positions as prime ministers in 1966. Brazil, Iran, the Philippines and Turkey also lost their positions as prime ministers. Chile, Mexico, Switzerland and the United States never had positions as prime ministers. This contrasts with the presidential system, in which the president (or equivalent) is both the head of state and the head of the government. In some presidential and all semi-presidential systems, such as those of China, France, Russia, South Korea or Ukraine, the prime minister is an official generally appointed by the president but usually approved by the legislature and responsible for carrying out the directives of the president and managing the civil service. The premier of the Republic of China (Taiwan) is also appointed by the president, but requires no approval by the legislature. Appointment of the prime minister of France requires no approval by the parliament either, but the parliament may force the resignation of the government. In these systems, it is possible for the president and the prime minister to be from