The United States appears to have no option but to take a neutral stance on the territorial row in simmering between Japan and South Korea, its two key allies in East Asia.

The row over the sovereignty of South Korean-administered Takeshima islets situated between the two countries flared up again when South Korean President Lee Myung Bak made an unprecedented visit to them Friday, underlining Seoul's territorial claim.

"The U.S. government's position for decades has been to not to take a position regarding the sovereignty of the Liancourt Rocks," a State Department official said, referring to the islets by the appellation issued by the U.S. Board on Geographic Names. The islets are called Takeshima in Japan and Dokdo in South Korea.