Allies China and Russia will hold joint naval drills later this week in the Sea of Japan, officials confirmed.
Experts say this reflects the deepened military cooperation between the two sides.
The two countries will conduct their largest joint Pacific exercise from August 20 to 28.
A Chinese squadron has left the port of Qingdao in Shandong province on Saturday and expected to dock at Russia’s Vladivostok on Thursday.
Phase II of Joint Sea Exercise 2015 will be held in both the Sea of Japan and off the coast of Russian region of Primorsky – about 250 miles away from Japan.
The drill will simulate protection of naval communications, anti-submarine training, air defense exercise and anti-ship maneuvers.
The Chinese unit consists of seven warships, six shipborne helicopters, five warplanes, 21 amphibious vehicles and 200 marines.
The Russian Pacific Fleet will be represented with up to 20 battleships and support vessels, two submarines, 10 warplanes, nine amphibious vehicles and also 200 marines, said broadcaster Russia Today.
Chinese military commentator Song Xiaojun says the location of the exercise is of strategic significance.
“The situation in the Sea of Japan has become volatile especially after US President Barack Obama announced the so-called Return to Asia plan three years ago and enhanced assistance to Japan. Taking into account Japan’s latest move to lift the ban on the right to collective defense that strengthens the Japan-US alliance and Russia-US confrontation in East Europe, tensions in the sea area may escalate. Meanwhile, the area neighbors Russia’s sparsely-populated Far East and China’s northeast that is undergoing rejuvenation, so both China and Russia want to enhance defense there,” he said.
Joint exercises between the two navies have become regular in recent years as part of the bilateral efforts for closer ties.
Last year saw the largest series of exercises that involved 14 surface ships, two submarines, aviation assets and special operation forces from the two sides.
The Pacific drills follow the first ever joint Chinese-Russian exercise in the Mediterranean Sea during the Joint Sea Exercise 2015 phase I this May.
The smaller exercise involved three warships from China and six from Russia and featured supply and escort drills.
Russian Pacific Fleet spokesman Roman Martov earlier said that the maneuvers will for the first time involve a joint amphibious assault drill with the participation of carrier-based aircraft.
The Sea of Japan borders four countries Japan, Russia, North Korea and South Korea.