Overview
There have been fifteen prime ministers of Sri Lanka since the creation of the position in 1947, prior to the independence of Ceylon. The prime minister of Ceylon was the head of the government until 1972. In 1972, the country was renamed as the Free, Sovereign and Independent Republic of Sri Lanka, and the position was known as the prime minister of Sri Lanka from then onwards. The prime minister also held the unified Ministry of External Affairs and Defence until 1977, when the government of J.R. Jayewardene split the ministry into two ministries, forming the Ministry of Defence and the Ministry of Foreign Affairs.
In 1978, after Jayewardene became the president, new constitutional changes were introduced. The position of the executive president was introduced, resulting in the powers of the prime minister being reduced. The president became the head of state and chief executive, and the prime minister became a weak head of government.
Under the current constitution of Sri Lanka, the prime minister is the leader of the Cabinet business and also functions as a deputy to the president. In the event a president dies in office, the prime minister becomes the acting president until the Parliament convenes to elect a successor or new elections can be held to elect a new president. Such was the case in 1993, when President Ranasinghe Premadasa was assassinated and Prime Minister Dingiri Banda Wijetunga took office as president.
On 28 April 2015, the Parliament approved the 19th Amendment to the Constitution of Sri Lanka which gives the power of the government to the prime minister, while the president remains the head of state, head of the Cabinet, and commander-in-chief.
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