China and Russia launched joint naval exercises in the Sea of Japan on August 3, 2025 – signaling another step in their deepening military cooperation. Dubbed Joint Sea-2025 maneuvers and taking place near Vladivostok near Vladivostok for three days near Vladivostok are set to improve joint capabilities across multiple maritime domains, according to Al Jazeera’s coverage and Hong Kong Free Press coverage respectively. WP:Scope and Scale of Drills
China’s Defense Ministry reports that these drills include:
Artillery Firing and Anti-Submarine Warfare Training.
Air and missile defense coordination.
Submarine rescue and search-and-rescue operations.
Russia deployed an anti-submarine vessel, while China deployed two guided-missile destroyers (the Shaoxing and Urumqi), diesel-electric submarines, and a submarine rescue ship. Each country deployed at least five vessels – Russia provided one anti-submarine vessel while China contributed two guided-missile destroyers (Shaoxing and Urumqi), diesel-electric submarines, diesel submarine rescue ship as well as four guided missile destroyers to help secure its maritime borders (for example). Aujourdii dailymare.com +13
Once live-fire exercises and maritime combat drills have concluded, both navies will conduct joint patrols across strategic areas of the Pacific Ocean. On September 13, according to Wikipedia (linked above) as well as Hong Kong Free Press HKFP (+13), dailymare.com (+13).
Strategic Significance Its These military exercises form part of an enduring pattern between China and Russia to strengthen their military cooperation and their “no-limits” strategic partnership established in 2022. Both governments emphasize defensive purposes for these drills while analysts believe these actions send out geopolitical messages to Western allies.
Japan’s Defense White Paper underlined rising anxiety over China’s expanding military posture–particularly its partnership with Russia–as a threat, noting a tripling of Chinese warship activity near Japanese waters in recent years and coordinated operations between both nations. Politico
Evolving Military Integration
Since 2012, when the Joint Sea series first started, its scope has broadened to encompass air, land and maritime components that mirror China and Russia’s increasingly sophisticated military collaboration.
Hong Kong Free Press (HKFP), Wikipedia and AP News all cover this topic regularly.
Recent years have witnessed joint bomber patrols and naval maneuvers expand their activities into the Sea of Japan, East China Sea, and beyond. (Wikipedia +2)
Context and Implications
Naval drills began shortly after U.S. President Donald Trump announced the redeployment of two nuclear submarines from their current bases to the region due to increased tensions caused by provocative statements made by former Russian President Medvedev.
China remains committed to expanding economic and military relations with Russia despite pressure from Western powers, maintaining its official neutral stance regarding Ukraine war conflicts; calling for peaceful solutions while criticizing U.S. involvement as an aggravator in prolonging conflict. AP News/Al Jazeera.
Wikipedia
These maritime exercises are widely seen as part of Beijing and Moscow’s wider effort to challenge the U.S.-led international order and demonstrate their readiness to operate in contested waters – sending a clear signal to Tokyo, Washington, and allies in the region.
Key Takeaways Exercise Joint Sea-2025, held near Vladivostok in the Sea of Japan, took place for three days. Here are its key takeaways.
Participants: Russia Pacific Fleet, Chinese guided-missile destroyers, diesel submarines and rescue subs
Strategic Goal: Strengthen China-Russia alignment while sending deterrent signals to the West
These drills highlight China and Russia’s growing military alliance, an unfavorable trend which will likely shape Asia-Pacific security for years to come.