Japan has protested against Russia's termination of years of negotiations with Japan over the territorial dispute over the Pacific archipelago of the South Kuril Islands.

"Russia's behavior is highly unwarranted and totally unacceptable.

We protest vehemently," said Japanese Prime Minister Fumio Kishida on Tuesday.

The Foreign Ministry in Moscow had described the step the day before as a reaction to "unfriendly steps".

Japan had joined Western sanctions against Russia's war of aggression in Ukraine.

Russia also canceled an agreement for visa-free travel by Japanese people to the Kuril Islands.

Japan has decided on an anti-Russian course, the ministry said in a statement in Moscow.

The relationship between the two countries has been strained for decades by the dispute over the Kuril Islands.

The archipelago lies between Russia's Kamchatka Peninsula and Japan's island of Hokkaido.

Japan had lost the islands to the Soviet Union after surrendering in World War II and lay claim to the four southern islands.

Russia, as the legal successor to the Soviet Union, rejects this.

The dispute has long prevented the conclusion of a peace treaty between Russia and Japan.

Kremlin boss Vladimir Putin once spoke out in favor of joint economic activities with Japan in the Kuril Islands.

That is now passé, it was said from Moscow.