日本新党
is a Japanese politician and former banker. He is a member of the House of Representatives in the Diet of Japan and previously served as leader of the Vision of Reform party, which he formed in December 2015. A native of Kofu, Yamanashi, he graduated from the University of Tokyo and received a master's degree in political science from Saitama University. Shortly after graduating, he studied economics and policy under Eisuke Sakakibara. Before joining the House of Representatives, he worked at Tokyo Bank and served as an advisor to several lawmakers. He was elected to the House of Representatives for the first time in 1993 as a member of Morihiro Hosokawa's Japan New Party. He was the Minister of the Environment during Yukio Hatoyama's prime ministership in 2009–2010.