China has criticized the United States for speaking out against a possible Chinese air defense zone over the South China Sea. China's Foreign Ministry spokesman Hong Lei said Air Defense Zones are often necessary to ensure air safety.

"Whether China will set up an air defence identification zone in the South China Sea in the future depends on whether its air safety is being threatened and the level of the threat as well as other reasons. At present, as I've said, the situation in the South China Sea is generally stable. We hope countries outside the region can support the efforts of China and ASEAN countries in safeguarding peace and stability in the South China Sea," Hong said.

US Deputy Secretary of Defense Robert Work said on Wednesday, the US would view any attempts by China to establish an Air Defense Zone over the South China Sea as "destabilizing" and would refuse to recognize it. Work also questioned China's right to setting up such a zone in the area. The US was the first country to set up an Air Defense Zone in 1950, at the start of the Cold War. Hong Lei has questioned Washington's right to create that zone.