MOSCOW - Moscow is closely monitoring Tokyo's naval presence near Russia's borders and is concerned over a potential shift in Japan's non-nuclear policy, Russian Foreign Ministry Spokesperson Maria Zakharova said on Wednesday.

Japan's plans to erode its non-nuclear status by joining US nuclear missions, holding multilateral exercises with the involvement of strategic aircraft for nuclear missions, and considering the deployment of US medium-range missiles on its territory are particularly concerning, Zakharova said during a weekly briefing.

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She said that Moscow was closely monitoring Tokyo's increased naval activities near Russia's borders in the Fast East with the involvement of North Atlantic Treaty Organization (NATO) members from outside the region.

Japan's policy ultimately poses concrete risks to regional stability and security, she added.