Japan on alert as three Russian ships push into Philippine Sea amid deepening Moscow–Beijing cooperation

Japan, a key US security ally, has detected Russian warships near its territory as Moscow begins a “long-range” mission in the Asia-Pacific region, Newsweek reports.

Japan’s Ministry of Defense reported that three Russian vessels — the frigate Marshal Shaposhnikov, the corvette Gremyashchiy, and a supply ship — passed between Japan’s remote Yonaguni and Iriomote islands, moving from the East China Sea to the Philippine Sea. Japanese forces have been tracking their presence near national waters since 3 October.

Moscow conducts "long-distance operations" 

According to Russia’s Pacific Fleet, the ships departed Vladivostok on 2 October for a “long-range deployment.”

The group also includes the fleet oiler Boris Butoma. During the mission, the vessels are expected to make port calls in foreign countries and conduct exercises, though the destinations have not been disclosed.

In addition, Japan’s surveillance forces recorded the Russian reconnaissance ship Karelia passing through the Tsushima and Miyako straits over the weekend, leaving the Sea of Japan for the Philippine Sea. It remains unclear whether this vessel is also part of the Pacific Fleet’s deployment.

Japan warns of increasing Russian military activity

In its 2025 Defense White Paper, Tokyo noted that Russian military forces continue active operations near Japan, showing readiness to deploy advanced equipment in the Far East.

"Russia's military activities in the Indo-Pacific region, including Japan, coupled with its strategic partnership with China, are posing a strong security concern," its statement stressed. 

Russia, meanwhile, claims the voyage aims to “carry out missions in the Asia-Pacific region.”

The open question remains how far Russia’s ships will operate during this deployment — and whether it could become another flashpoint in the already unstable Indo-Pacific region.