A move by Japan to provide Patriot air defence systems to Ukraine will have "grave consequences" for Russia-Japan ties, Russian foreign ministry spokeswoman Maria Zakharova said on Wednesday.

Relations between Moscow and Tokyo, already difficult, have deteriorated sharply since Russia sent tens of thousands of troops into Ukraine in Feb. 2022. Japan has joined its Western allies in imposing sweeping economic sanctions on Russia.

Last week, Japan said it would prepare to ship Patriot air defence missiles to the United States after revising its arms export guidelines, in Tokyo's first major overhaul of such export curbs in nine years.

Although Japan's new export controls still prevent it from shipping weapons to countries that are at war, it may indirectly benefit Ukraine in its war with Russia as it gives the United States extra capacity to provide military aid to Kyiv.

"The Japanese side loses control over the weapons with which Washington can now do whatever it wants," Zakharova told a weekly briefing. "It cannot be ruled out that under an already tested scheme Patriot missiles will end up in Ukraine."

Such a scenario would be "interpreted as unambigously hostile actions against Russia and will lead to grave consequences for Japan in the context of bilateral relations", she said.

Earlier this month, Japan and South Korea both scrambled jets to monitor joint flights by Chinese and Russian bombers and fighters near their territories.

Russia and Japan have yet to conclude a treaty formally ending World War Two hostilities due to an old territorial dispute involving a chain of Pacific islands known in Japan as the Northern Territories and in Russia as the Southern Kuriles.

Even before the Ukraine conflict, Tokyo had complained about increased Russian military deployments on the islands, which the Soviet Union seized from Japan at the end of World War Two.

Reuters

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