The Finance Ministry's top currency diplomat Masatsugu Asakawa has been tapped to become vice finance minister, its highest bureaucratic post and one that has remained vacant since April, sources close to the matter said.

The appointment of Asakawa, 60, goes against the ministry's typical order of succession and underscores the disarray wrought by the resignation of his predecessor, Junichi Fukuda, over allegations that he sexually harassed a female journalist.

Asakawa is known as a close aide of Finance Minister Taro Aso, having served as his personal secretary during Aso's stint as prime minister.

He will be replaced as vice finance minister for international affairs by Yoshiki Takeuchi, 58, the current head of the ministry's International Bureau.

Vice finance ministers are most often succeeded by the head of the powerful Budget Bureau, but current chief Shigeaki Okamoto was apparently deemed unfit for the role because he was in a supervisory position during a document tampering incident related to a controversial public land sale — a scandal which has been shaking not only the ministry but the administration of Prime Minister Shinzo Abe.

The heavily discounted sale of a plot of land in Osaka Prefecture to Moritomo Gakuen, a nationalist school operator with ties to Abe's wife, and subsequent document doctoring led to the resignation of Nobuhisa Sagawa, head of the National Tax Agency, in March.