Secretary of State John Kerry and Secretary of Defense Chuck Hagel responded to China's announcement of its Air Defense Identification Zone, which includes territories administered by Japan and South Korea. On December 5, 2013, The U.S. Senate Foreign Relations Committee sent the Chinese Ambassador Cui Tiankai a letter urging the Chinese government not to implement an Air Defense Zone in the East China Sea. The U.S.-China Economic and Security Review Commission released a report on January 14 , 2014 to analyze China's purpose in announcing its ADIZ.
The United States is deeply concerned by the People's Republic of China announcement today that it is establishing an air defense identification zone in the East China Sea. We view this development as a destabilizing attempt to alter the status quo in the region. This unilateral action increases the risk of misunderstanding and miscalculations.
"This announcement by the People's Republic of China will not in any way change how the United States conducts military operations in the region.
"The United States is conveying these concerns to China through diplomatic and military channels, and we are in close consultation with our allies and partners in the region, including Japan.
"We remain steadfast in our commitments to our allies and partners. The United States reaffirms its longstanding policy that Article V of the U.S.-Japan Mutual Defense Treaty applies to the Senkaku Islands."