Chinese Navy submarine rescue ship Xihu in joint search & rescue drills with Russian Navy

The joint Russian-Chinese naval exercises "Maritime Interaction-2025" took place in the Sea of Japan from August 1 to August 5, 2025, marking an intensification of military cooperation under the "no-limits" strategic partnership the two countries signed shortly before Russia's 2022 invasion of Ukraine. 

These drills, which have been held regularly in recent years, are designed not only to enhance operational coordination and expertise between the Russian Navy and the People's Liberation Army Navy (PLAN), but also to signal strategic deterrence to other global and regional powers, particularly given ongoing tensions surrounding the Ukraine conflict and the wider security environment in East Asia.

A key focus of the 2025 iteration was anti-submarine warfare (ASW), with notable involvement of advanced naval assets from both sides. The Chinese Navy’s submarine rescue vessel Xihu took part in joint search and rescue drills alongside other participating ships.

The exercises also incorporated an expanded coastal phase, featuring a newly established joint headquarters in Vladivostok, Russia. There, planners from both nations coordinated operations, both on maps and at sea—a setup implemented for the first time in the history of these drills.

During these exercises, Russian and Chinese forces practiced detecting, hunting, and mock-destroying an "enemy" submarine. The scenario involved Chinese Y-8 anti-submarine aircraft and Russia’s Il-38 naval patrol planes, supported by helicopter crews and surface ships from both navies.

According to the Russian Ministry of Defence, “as a result of effective joint actions, the ‘enemy’ submarine was promptly detected and mock-destroyed,” followed by mutual recognition of the crews for their “fruitful work”. Alongside the ASW operations, the navies also coordinated search and rescue practices, air defence manoeuvres, and joint artillery firing against simulated sea and aerial targets.

The context surrounding these drills added further significance. The exercises occurred just days after U.S. President Donald Trump publicized his order relocating two U.S. nuclear submarines closer to the region, a move he stated came in response to “highly provocative” remarks by former Russian president Dmitry Medvedev about the risks of nuclear conflict.

The Kremlin publicly downplayed Trump’s announcement, emphasizing that U.S. nuclear submarines are always on alert and warning against reckless nuclear rhetoric. Meanwhile, Trump threatened additional sanctions on Russia and on buyers of its oil, including India and China, unless Russia ends the ongoing war in Ukraine by a set deadline, heightening diplomatic stakes.

This iteration of "Maritime Interaction" also uniquely featured an expanded coastal phase with shore-based planning, and the participation of an unidentified Chinese submarine—reportedly of the Russian-built Project 636 class—demonstrating a degree of technical interoperability between the two navies. The command structure saw Russia’s Admiral Tributs anti-submarine warfare ship leading its fleet, while the PLAN’s Shaoxing destroyer commanded the Chinese formation.

“Maritime Interaction-2025” showcased enhanced integration in joint command, advanced anti-submarine and rescue coordination, as well as a visible display of strategic deterrence amid rising international tension.

Russia and China, through these regular exercises, continue to rehearse complex naval scenarios, building a foundation for more seamless operational cooperation in the event of serious maritime contingencies, while simultaneously sending geopolitical signals to the United States and its allies regarding the depth and capabilities of their partnership.

International Agencies