Sea. While Washington's defense chief spoke out

against China's increasing assertiveness in the region,.. his Chinese counterpart warned

his country was prepared to use its military if it feels threatened.

Yoo Li-an reports. In a clear display of the underlying tensions

between the two world superpowers, the defense chiefs of China and the United States on Tuesday

exchanged some sharp words on territorial disputes.

U.S. Defense Secretary Chuck Hagel denounced Beijing's declaration of an air defense zone

over the East China Sea,.. that includes the disputed islands known as Diaoyu in China

and Senkaku in Japan.

"Every nation has a right to establish an air defense zone, but not a right to do it

unilaterally with no collaboration, no consultation. That adds to tensions, misunderstandings,

and could eventually add to, and eventually get to dangerous conflict."

Hagel added that in case of conflict with Japan,.. the U.S. will protect its ally, as

laid out by its treaty obligations. China's Defense Minister fired back saying

Beijing stands ready to assemble its military to protect its territory.

"I'd like to reiterate that the territorial sovereignty issue is China's core interest.

On this issue we will make no compromise, no concession, no trading, not even a tiny

bit of violation is allowed."

Chang also said the U.S. should not be permissive or supportive of Tokyo.

China-U.S. relations have been under strain since Beijing's unilaterally declared its

air defense zone last year. Prior to his trip to Beijing, Defense Secretary

Hagel expressed support for Japan's claims to the disputed territory in the East China

Sea. Yoo Li-an, Arirang News.