Protesters yelled patriotic slogans on the steps of Japan's unofficial embassy in Taipei Tuesday as Taiwan's leaders vowed never to bow to Tokyo's will in a dispute over a deserted chain of islands.

Japan said it was tightening patrols around the islands, called Diaoyutai in Chinese and Senkaku in Japanese, expecting further Taiwanese attempts to challenge its sovereignty."The islands are Japanese territory and it is our duty to keep our eyes on them," an official of Japan's Maritime Safety Agency in Tokyo said.

In Taipei Premier Hau Pei-tsun warned legislators against "showmanship" in what threatens to become a domestic political crisis. But he repeated his intention to protect Taiwan's integrity.