A candidate who opposes the relocation of an American air base on Okinawa won a crucial mayoral election on Sunday, raising pressure on Japan’s Prime Minister to move the base off the island, a move opposed by the United States.

The election in the small city of Nago could force Japan to scrap, or at least significantly modify, a 2006 deal with the United States to build a replacement in Nago for the busy Futenma U.S. Marine air station, currently in a crowded part of the southern Japanese island.

The fate of that deal has already become the focus of a growing diplomatic rift between the United States and Japan, its closest Asian ally. The Obama administration has been pushing Japan to honour the deal, but the new Prime Minister, Yukio Hatoyama, has said he will take until May to decide whether to support it or name a new site.

Political experts have said losing Nago as a site for the base would complicate Mr. Hatoyama’s decision, because few other Japanese communities appear willing to host the base and its noisy helicopters. This means that Mr. Hatoyama could try to merge the Marine base with a nearby U.S. Air Force base, or move it to Guam; both are options that the Obama administration has resisted.

Before his Democratic Party’s historic victory in national elections last summer, Mr. Hatoyama campaigned on promises to move the base off Okinawa or out of Japan altogether. In doing so, he was tapping deep misgivings in Japan about the 2006 agreement, which was signed by Mr. Hatoyama’s predecessors, the Liberal Democrats. Many Japanese say the move to Nago would cause excessive environmental damage and impose an unfair burden on Okinawa, where almost half of the 50,000 U.S. military personnel in Japan are located.

On Sunday, Susumu Inamine, the city’s school board chairman and an opponent of the base, defeated the incumbent mayor, Yoshikazu Shimabukuro, who supports it as a source of jobs and investment. — © 2010 The New York Times News Service

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