BEIJING - China's newly-established air defense identification zone over the East China Sea does not target a specific country, said a military expert in Beijing on Tuesday.

"Other nations do not need to be alarmed," said Zhang Junshe, an expert with the navy, in an interview with Xinhua.

The establishment of the East China Sea Air Defense Identification Zone is not related to the situations around the Diaoyu Islands and should not be considered a countermeasure against Japan, Zhang said.

As a necessary measure to protect China's sovereignty and security, as well as a common international practice, the air defense zone is completely out of the need for self-defense, he said.

Neighboring countries around China, such as Japan, the Republic of Korea, The Philippines and Vietnam, have set up their own air defense identification zones before China, according to Zhang.

Since every country has an equal right to protect its sovereignty and security, the principle of "first come, first served" should not be applied on air defense identification zones, said Chai Lidan, an expert with the air force.

When explaining why the zone is located as close as 130 kilometers to some countries, China's Defense Ministry spokesman Yang Yujun said on Saturday that from the east end of the zone, which is still close to China, combat aircraft can reach China's airspace within a short time, so it is necessary for China to identify an aircraft from that point to ascertain its purpose and attributes.

Chai told Xinhua that, for two close neighbors like China and Japan, it is inevitable that their air defense zones will overlap.

The air defense identification zone, which is demarcated outside the territorial airspace, is not exclusive, so an overlapping area is allowed, Chai said.

In the overlapping areas, the two countries should communicate well with each other and jointly protect flight security, he said.

However, he denied the overlapping of China's and Japan's air defense zones over the Diaoyu Islands.

The air defense zone set up by Japan over the Diaoyu Islands is illegal, as the islands belong to China and the airspace over them is China's territorial airspace, rather than part of the air defense zone of another country, he said.

China announced its decision to establish the East China Sea Air Defense Identification Zone on Saturday.