Kerry renewed the security pledge related to the islets, known as the Senkakus in Japan and the Diaoyus in China, at a New York news conference with Japan's foreign and defense ministers to unveil updated U.S.-Japan defense guidelines on the eve of Prime Minister Shinzo Abe's talks with President Barack Obama.
"It's an historic transition in the defense relationship between our two countries," Kerry said.
The new guidelines for defense cooperation reflect Japan's willingness to take on a more robust international role at a time of growing Chinese power and rising concerns about nuclear-armed North Korea.