Russia has warned Japan that it could face countermeasures if U.S.-made Typhon missile systems are deployed on Japanese territory, saying such weapons pose a direct threat to Russian national security.

Foreign Ministry spokeswoman Maria Zakharova said Moscow had formally informed the Japanese Embassy that the deployment of the missile system, even temporarily for military exercises, would be "absolutely unacceptable."

Speaking on the sidelines of the Eastern Economic Forum in Vladivostok, Zakharova said Russia would take retaliatory measures necessary to safeguard its national security if the deployment proceeds.

The warning follows the temporary deployment of the U.S. Army's Typhon missile system to Kanoya Air Base in Japan's Kagoshima Prefecture during the Valiant Shield military exercises earlier this year, according to Japanese media.

The Typhon system is capable of launching Tomahawk land-attack cruise missiles with a range of up to 1,600 kilometers, making it the longest-range ground-based missile system deployed in Japan. It can also fire SM-6 missiles designed for air defense and long-range precision strikes.

Zakharova urged Japan to return to what she described as its post-war pacifist policy and reiterated that Russia's sovereignty over the Southern Kuril Islands is "non-negotiable."

She also said the Russian Foreign Ministry had lodged a diplomatic protest with the Japanese Embassy on Monday over planned military exercises involving the missile system.

The latest warning reflects growing tensions between Moscow and Tokyo over regional security, as Russia has repeatedly criticized the expansion of U.S. military capabilities in the Asia-Pacific region and closer defense cooperation between Japan and the United States.(ILKHA)