South Korea's prime minister Han Seung-soo (C) and other officials celebrate after they installed a sign stone on the small cluster of islands, called Dokdo in Korean and Takeshima in Japanese, July 29, 2008. South Korea's prime minister on Tuesday visited to a set of desolate islands at the centre of a territorial tussle with Japan and criticised a US government agency for shifting its position on their ownership. The long-burning dispute over the rocky outcrop erupted again this month after an official school history guide in Japan referred to the islands as Japanese territory, triggering angry demonstrations in Seoul and an official protest from South Korea. The sign stone reads,"Our Land, Dokdo on the East Sea". [Agencies]