Two crewmen stand on the deck of one of seven Chinese warships which arrived in Russia's Far Eastern port of Vladivostok on Friday. China and Russia Friday started eight-day joint naval drills off the coast of Russia's Far East. It will be the largest maneuver China has ever held with a foreign navy. Photo: CFP

The Chinese and Russian navies Friday started their largest-ever joint drills in the Sea of Japan, prompting concerns from Japan, which has territorial disputes with both countries.

A fleet of seven Chinese warships, including four destroyers, two frigates and a supply ship, arrived in Russia's Far Eastern port of Vladivostok Friday morning, kicking off eight days of naval drills with Russia.

Addressing a welcoming ceremony at a naval port of Russia's Pacific Fleet, Leonid Sukhanov, deputy chief of staff of the Russian Navy, said the drill, dubbed "Joint Sea-2013," is one of the largest joint military maneuvers in the region, Xinhua reported.

"The two navies can withstand any invasion and cope with any challenge," Sukhanov was quoted by Phoenix TV as saying.

According to Xinhua, Ding Yiping, deputy commander of the People's Liberation Army Navy, said the maneuvers would deepen the strategic partnership between China and Russia and military-to-military relations.

"China and Russia both face some security problems and threats at sea. Through the joint drills, we can raise our capacities in tackling such security threats," Ding said, adding they could also enhance the two navies' capability in coordinating maritime defense operations.

A total of 19 vessels, eight planes and two special forces teams from the two countries will participate in the exercises in Peter the Great Bay in the Sea of Japan. The maneuvers will focus on joint maritime air defense, joint escorts and marine search and rescue operations, Xinhua reported.

Ding reiterated that the joint exercises are not targeting any third party, and those who feel uneasy have "a guilty conscience."

Tensions between Japan and China were heightened since last September after Tokyo unilaterally "nationalized" the Diaoyu Islands in the East China Sea, while Russia and Japan also have disputes over a group of islands, known as the Southern Kuriles in Russia and the Northern Territories in Japan.

According to the Tokyo-based Chinese-language news portal ribenxinwen.com, Japanese Chief Cabinet Secretary Yoshihide Suga Friday told a press conference, "We are very concerned about the drills, and are collecting and analyzing related intelligence."

The news portal said the Japan Self-Defense Force has sent scouts and early warning aircraft for 24-hour surveillance along the Japanese side of the Sea of Japan and in airspace near Hokkaido. Meanwhile, frigates from the Japan Maritime Self-Defense Force also headed to the area to collect information on the Sino-Russian drills.

According to Kyodo News, Japan and the US will hold joint air combat drills in the airspace over Hokkaido from Monday to Friday. Eight F-15 fighters from Japan and eight F-16 fighters from the US will participate in the exercises.

Du Wenlong, a military expert, told China Central Television (CCTV) that when the Chinese fleet Wednesday sailed through the Tsushima Strait, Japan's P-3 aircraft and warships were following them from a close distance.

The Chinese and Russian navies will reportedly carry out combat exercises and enter the Sea of Japan from Saturday to Monday, but it is still unclear if they will sail across the La Perouse Strait dividing the southern part of the Russian island of Sakhalin from the northern part of the Japanese island of Hokkaido.

Zhang Junshe, a research fellow with the Chinese Naval Research Institute, told the Global Times earlier this week that the Sino-Russian naval drills do not include any island retaking maneuvers like the US-Japan exercises always do.

"The drills are defensive in nature and don't target any third party," Zhang said.

The two navies sent their main vessels to the maneuvers.

Six of the seven Chinese vessels have been on active service since the beginning of the century. Russia's vessels, led by the Varyag cruiser, dubbed the "aircraft carrier killer," also represent the Russian Navy's current fighting capacity, Xinhua quoted experts as saying.

Song Xiaojun, a military commentator, told CCTV that the exercises could serve as a deterrent to some countries' attempts to turn the Western Pacific into the battlefield of a new Cold War.

It is the second time China and Russia have held naval drills. In 2012, the they conducted drills in the Yellow Sea.