Kim, a Korean-American, will be contesting against two nominees from emerging market countries - Nigerian Finance Minister Ngozi Okonjo-Iweala and former Colombian Finance Minister Jose Antonio Ocampo - for the Washington-based institution's top job.

"We decided he is an extremely suitable candidate for the World Bank presidency and we will support him," Azumi said, stressing his track record working on HIV/AIDs issues with the World Health Organisation.

Azumi said that the right candidate for the job would understand Japan's stance as a major contributor country and would be able reflect that in the World Bank's policies.

Kim, a physician and anthropologist, was named by the Obama administration in March as the U.S. pick to succeed Robert Zoellick when he steps down in June.

By tradition, an American has headed the World Bank since its founding after World War Two, but the emerging economies are increasingly open about challenging that convention.

"Mr Kim's mother and father are from the Korean Peninsula. He is of course the U.S. nominee, but he also fully understands the position of developing countries heaving spearheaded the efforts to eradicate AIDS at the WHO," said Azumi in a bid to reassure emerging economies.

Next on the agenda of Kim's "listening tour" as the U.S. Treasury Department calls the trip, is Seoul, New Delhi, Brasilia and Mexico City. He is touring the world between March 27 and April 9 to meet heads of state, finance ministers and others to talk about priorities for the World Bank.

The candidate is the president of Ivy League university Dartmouth College, was born in South Korea, but moved to the United States as a boy.

(Reporting by Antoni Slodkowski; Editing by Ed Lane)

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