Japan plans to support Jim Yong Kim, the US nominee for World Bank president.
Japanese finance minister Jun Azumi expressed the country's support for Kim after the pair met in Tokyo, Reuters said.
Kim has been touring Asia to drum up support for his candidacy.
He is competing for the World Bank's top job against two candidates from emerging market countries - Nigerian Finance Minister Ngozi Okonjo-Iweala and former Colombian Finance Minister Jose Antonio Ocampo.
Since the organizations were founded after World War II, an American has traditionally headed the World Bank while a European has headed the International Monetary Fund. But emerging market economies have been pushing for a larger voice at the World Bank and the International Monetary Fund as their economic clout has grown.
The BRICS - Brazil, Russia India, China and South Africa - have even discussed putting forward their own candidate to takeover as the World Bank's next president.
More from GlobalPost: BRICS consider their own candidate for top World Bank job
The World Bank board is set to make its decision in mid-April, Bloomberg said.
Current World Bank President Robert Zoellick is stepping down this summer.
More from GlobalPost: The Argentine economy's fuzzy math problem