Russian President Vladimir Putin’s disputed visit to the Kuril Islands has renewed tensions between Japan and Russia, according to a report published on August 18, 2026. Japan responded strongly to the visit, while Moscow summoned Japan’s ambassador in a countermeasure. Japanese Prime Minister Sanae Takaichi called Putin’s trip “completely unacceptable.”

Japan claims four islands in the southern part of the Kuril chain as its own territory, referring to them as the Northern Territories. Russia regards the islands as part of its Kuril Islands. The dispute has continued since the final stage of World War II, when the Soviet Union seized four islands near Japan.

The contested area is important for historical and political reasons, as well as for its rich fisheries and potential valuable mineral resources. Its location between the Sea of Okhotsk and the Pacific Ocean is strategically important to Russia and supports the movement of its Pacific fleet. The report says this was Putin’s first visit to the islands after a long time in power. Analysts say bilateral relations had already deteriorated after Japan imposed sanctions on Russia following the Ukraine war.