????QINGDAO, Aug. 15 (Xinhua) -- Seven Chinese warships on Saturday left east China's port of Qingdao for the Sea of Japan where they will join Russian counterparts on a nine-day exercise.

????The drills, codenamed Joint Sea-2015 (II), will take place from Aug. 20 to 28 in the Peter the Great Gulf, waters off the Clerk Cape, and the Sea of Japan.

????This will be the second China-Russia naval exercise this year.

????A source close to the operation said navies of the two countries will join forces to simulate anti-submarine combat and air defense and other relevant missions. A joint beach landing of troops is also planned.

????The source said the drills "are not targeted at any third party and are not relevant to regional status-quo."

????"The drills are part of annual exchange program between Chinese and Russian militaries," the source said.

????The Chinese fleet includes destroyers Shenyang and Taizhou, frigates Linyi and Hengyang, landing craft Changbaishan and Yunwushan and supply ship Taihu. They will arrive at the Russian port of Vladivostok on Aug. 20 where the two navies will hold cultural and sporting activities.

????Six helicopters, five fixed-wing aircraft, 21 units of amphibious equipment and 200 marines will also join the exercise from the Chinese side.

????The Russian navy, meanwhile, will send 16 surface ships, two submarines, 12 naval aircraft, nine amphibious vehicles and 200 marines.

????Chinese and Russian navies have held five joint exercises since 2005.

????The last China-Russia naval drills, Joint Sea-2015 (I), were held in the Mediterranean Sea in May.