MOSCOW – Russia has warned of possible countermeasures over Japan's deployment of US Typhon missile systems, Russian Foreign Ministry spokeswoman Maria Zakharova said on Tuesday.

"The Japanese Embassy was clearly informed that the deployment of this type of weaponry on Japanese territory, even under the pretext of military exercises, is absolutely unacceptable, as it poses a threat to Russia's security," Zakharova told a briefing on the sidelines of the Eastern Economic Forum in Vladivostok, adding that Moscow had warned of retaliatory measures to ensure national security.

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The Typhon missile system, deployed by the Kanoya Air Base in Kagoshima Prefecture for the Valiant-Shield exercises, is capable of carrying Tomahawk missiles with a range of up to 1,600 km, Japanese media reported at the end of June. It is the longest-range ground-based weapons system deployed in Japan.

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Calling on Japan to return to its pacifist policy, Zakharova reiterated that Russian sovereignty over the Southern Kuril Islands was beyond question. She said the Russian Foreign Ministry had lodged a diplomatic protest with the Japanese embassy on Monday over the planned military exercises.