China has recently adjusted the country's air defense zone over the East China Sea, something that neither Japan nor the United States seem to agree with.

According to CNN, China said that it had sent fighter jets to identify U.S. and Japanese planes that recently flew through the new zone without identifying themselves.

The zone expanded into areas of the East China Sea that are currently being disputed by both China and Japan and is near the U.S. military base on Okinawa. The zone also covers the Senkaku Islands, which both Asian countries claim is theirs.

Since the declaration of the new zone, 10 Japanese and two U.S. surveillance planes have crossed into the territory in defiance of China's new declaration. Two Japanese airlines have also rejected the new zone.

China's move to follow jets crossing into the air defense zone is in line with warnings that the country would use "defensive emergency measures" towards anything aircraft to identify itself, reports Reuters.

Professor Shi Yinhong, of Renmin University who helps advice Beijing's State Council, noted that it will be interesting to see how the zone is recognized by the U.S. over time. "How the U.S. and its allies recognize that will be vital to the future of the region."

Yinghong added, "This (zone) could cause the U.S. to have more profound strategic thinking about China's rise."