Photo shows People's Liberation Army Navy participating in the China-Russia Joint Sea-2025 naval exercise at Vladivostok, Russia on August 1, 2025. Photo: Xinhua

China and Russia kicked off the full maritime phase of the Joint Sea-2025 naval drills on Sunday. Vessels from both countries set sail from a military port early in the morning, heading to waters near Vladivostok, Russia, to carry out multi-domain exercises. A Chinese military affairs expert said that the exercise, which includes submarine-related training, is expected to further enhance the interoperability between the two navies.

The participating Chinese and Russian naval formations set sail from a military port on Sunday morning toward waters near Vladivostok, Russia, to carry out multi-subject drills, marking the full-scale launch of the maritime portion of the Joint Sea-2025 exercise, according to China Bugle, an official media account affiliated with the PLA News Media Center, according to the WeChat account of the Chinese Defense Ministry.

At around 5 am, with support from Russian tugboats and port personnel, China's comprehensive rescue ship Xihu and Russia's rescue ship Igor Belousov were the first to leave port. They were followed by China's Type 052D guided-missile destroyers Shaoxing and Urumqi, and Russia's large anti-submarine ship Admiral Tributs and the corvette Rezky, the report said.

Upon departure, the vessels quickly formed a mixed China-Russia formation in accordance with the joint coordination plan and proceeded to the designated mission area. On the open sea, Chinese and Russian vessels established communication links and exchanged vital information including hydrometeorological conditions and maritime and air activity.

Prior to this, the joint command formed by both sides conducted a chart-based rehearsal in accordance with the exercise plans. Discussions focused on the organization structure and force coordination, with both sides working to refine the drill subjects and safety protocols. Professional exchanges were also held on topics such as undersea offense and defense, as well as submarine rescue operations, according to the report.

According to the exercise schedule, the China-Russia naval formation will conduct a three-day maritime drill. The exercise will cover subjects including submarine rescue, joint anti-submarine warfare, air and missile defense, and naval combat. Live-fire training will also be conducted to test the planning and coordination outcomes achieved during the preparatory phase, the report said.

This is part of the annual cooperation plan between the Chinese and Russian militaries, which is not targeted at any third party, and is unrelated to the current international and regional situations, Senior Colonel Zhang Xiaogang, a Chinese Defense Ministry spokesperson, said at a regular press conference on Wednesday.

Ten editions of China-Russia Joint Sea drills have been successfully held since 2012, as the series has become an important platform for China-Russia naval cooperation, promoting maritime joint operational capabilities from all directions, also noting that the two sides will hold a maritime joint patrol in Western Pacific waters following the exercise, CCTV News reported.

Wang Yunfei, a Chinese military affairs expert, told the Global Times that China and Russia regularly hold joint maritime exercises, with each iteration featuring different training courses to enhance coordination capability and interoperability between the two navies, as well as deepen bilateral military ties.

As China Bugle also stated that the drill will include submarine rescue and joint anti-submarine operations, it is likely that submarines are participating as well, Wang said, noting that conducting submarine-related training can be seen as a sign of deepening ties and mutual trust between the Chinese and Russian militaries.