Toshiki Kaifu, Japan's prime minister for about two years from 1989, died earlier this month, the government said Friday. He was 91.

Kaifu, best known for sending the Maritime Self-Defense Force to the Persian Gulf in 1991 in the SDF's first war-related overseas mission, died Sunday of natural causes, the House of Representatives said.

Toshiki Kaifu. (Kyodo)

"He dedicated himself to tackling many policy challenges amid a turbulent international situation, including the outbreak of the Persian Gulf War," Chief Cabinet Secretary Hirokazu Matsuno said in offering condolences during a regular news conference.

Kaifu, who loved wearing a polka-dot necktie, was close to former Prime Minister Takeo Miki and had an image of being politically clean.

The reputation helped him win the premiership in August 1989 after his predecessors Noboru Takeshita and Sosuke Uno were knocked from power over a major insider trading and corruption scandal and an extramarital affair scandal, respectively.

The Nagoya-native started his political career as a lawmaker's secretary and was first elected to the lower house in 1960 on the ticket of the Liberal Democratic Party. Before becoming prime minister, he served in key government posts, including deputy chief Cabinet secretary and education minister.

Under his leadership, Japan made the key decision to send the SDF to the Persian Gulf after being criticized for engaging in "checkbook diplomacy" after it gave $13 billion to coalition forces in the U.S.-led 1991 Persian Gulf War rather than contributing personnel.

Recently declassified diplomatic records show then U.S. President George H.W. Bush directly urged Kaifu to provide logistical support to the U.S. military via the SDF in the wake of the 1990 Gulf crisis, despite restraints imposed by Japan's pacifist Constitution.

In the end, the SDF took part in a minesweeping operation in the Persian Gulf as a postwar contribution, resulting in a diplomatic turning point for Japan. In 1992, Tokyo promulgated legislation enabling its participation in United Nations peacekeeping operations, and the country has joined such missions overseas ever since.

On the domestic front, Kaifu tried to carry out political reforms, including introducing single-seat constituencies in elections.

But he was forced to step down as premier in November 1991 after a key bill for bringing about the change failed to pass parliament. The bill was eventually passed in 1994, creating the single-seat constituency system along with the proportional representation scheme.

Kaifu left the LDP in 1994 and became the leader of the now-defunct New Frontier Party, which he formed with Ichiro Ozawa and others, but returned to the LDP in 2003. He retired from politics after losing his seat in the lower house election in 2009.

Japanese Prime Minister Toshiki Kaifu (L) shakes hands with British counterpart Margaret Thatcher in Tokyo in September 1989. (Kyodo)

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