The Foreign Ministry on Tuesday named Hitoshi Tanaka, director general of the economic affairs bureau, as head of the bureau in charge of Asian and Oceanian affairs.
Shinichi Kitajima, minister at the Japanese Embassy in the United States, will replace Tanaka.
The two appointments were approved by the Cabinet in the morning and took effect the same day.
Tanaka, 54, has served as director in the Northeast Asia division and the Foreign Policy bureau's policy coordination division. He was consul general in San Francisco before being appointed head of the economic affairs bureau in January 2000, the ministry said.
He replaces Kunihiko Makita, who is at odds with Foreign Minister Makiko Tanaka and has hardly spoken to her recently, according to ministry sources.
Makita was assigned to the foreign minister's secretariat effective Tuesday.
Kitajima, 55, held various posts in the economic affairs bureau before becoming consul general in Boston and then minister at the Japanese Embassy in Washington in February last year, the ministry said.