SEOUL, June 23 (Xinhua) -- South Korean former prime minister Kim Jong-pil died Saturday at the age of 92, his aid and hospital officials said.

Kim was sent to a hospital in central Seoul on Saturday morning, but was confirmed dead before the arrival, local media quoted hospital officials as saying, adding that he was believed to die of old age.

The presidential office Cheong Wa Dae expressed condolences on Saturday over the death of the former prime minister.

Along with two former presidents - Kim Young-sam and Kim Dae-jung, Kim Jong-pil has been cited as one of the three influential figures having had a major effect on the country's political landscape in a period referred to as the "Three Kims" era.

At the age of 35, Kim, husband of a niece of former President Park Chung-hee, made his first mark on South Korean politics in 1961 when he participated in a military coup led by Park, who later ruled the country in the 1960s and 1970s.

Kim later served as head of the country's main intelligence agency and prime minister during Park's rule, when he was known as the "No.2 man."

In October 1979, Park Chung-hee was assassinated. Under the then new government, Kim was banned from all public positions and all political activity.

His political exile ended in 1987 and he ran unsuccessfully for president. In 1995, he founded the United Liberal Democrats and became the party's president.

Kim and his party joined forces with Kim Dae-jung for the 1997 presidential election. To cement the successful alliance, Kim Jong-pil was appointed prime minister for the second time in his career.

He left politics in 2004, taking responsibility for his party's defeat in the election in the year.