The six days of exercises began on Sunday from the East China naval base of Qingdao on the Yellow Sea. The drills were meant to focus on joint air defense, anti-submarine tactics and search-and-rescue operations, Chinese state media said. Anti-terror operations and the freeing of hijacked vessels were also expected to be simulated.

Sixteen Chinese ships, two submarines and 4,000 troops were taking part in the maneuvers, state news agency Xinhua said, while Russia had sent seven vessels, including four warships.

"This joint military exercise is a long-scheduled one between China and Russia in order to uphold regional peace and stability," Chinese foreign ministry spokesman Liu Weimin said at a news briefing.

The two countries took part in war games together in 2005, but these are the first joint naval exercises.

Concern in Asian seas

The maneuvers are taking place as disputes simmer between China and numerous neighbors over territorial claims to islands in waters rich in fish - and possibly in natural resources, too.

Beijing and Tokyo are at odds over a chain of islands, called Diaoyu by China and Senkaku by Japan, in the East China Sea. China also has disputes with Vietnam and the Philippines over islands in the Yellow Sea.

Earlier this month, a row between China and the Philippines over an uninhabited shoal flared up in a tense standoff between ships from the two countries.

ncy/tj (AFP, dpa )