Singapore | Economist Lawrence Wong was on Wednesday sworn in as Singapore's fourth prime minister in a planned political transition for the island state.

Wong, 51, succeeded Lee Hsien Loong, 72, who relinquished his position after two decades; both belong to the ruling People's Action Party (PAP) that has been driving Singapore's economic progress for more than five decades.

Wong, who was the deputy prime minister, will be leading the fourth generation PAP politicians' government as the Prime Minister and the Finance Minister.

President Tharman Shanmugaratnam, 67, administered the oath to Wong, described by the local media as a low-key leadership transition.

Wong cited continuity, stability and the need to avoid disruptions as reasons for not making major changes at the minister (cabinet) level.

"With all other ministers holding on to their portfolios across the leadership transition from Lee Hsien Loong's government to Wong's, it also testifies to the consistency in Wong's decision-making,” a Channel News Asia report said.