The United States is obligated to defend the Senkaku Islands, controlled by Japan but claimed by China.

The United States is obligated to defend the Senkaku Islands on behalf of Japan, new U.S. Secretary of State Rex Tillerson told Foreign Minister Fumio Kishida in their first telephone conversation on Feb. 7. The Senkakus, in the East China Sea, are controlled by Japan but claimed by China. They are covered by Article 5 of the Japan-U.S. Security Treaty, which obliges the United States to defend Japanese territories, Tillerson said.