The Japanese government has reacted angrily to Vladimir Putin’s first visit to the disputed Kuril Islands, which are claimed by both Tokyo and Moscow.Japan’s foreign minister, Toshimitsu Motegi, summoned the Russian ambassador Nikolay Nozdrev, while the prime minister, Sanae Takaichi, called Putin’s actions “absolutely unacceptable”.Known in Japan as the Northern Territories and by Russia as the Southern Kurils, the islands were seized by the then Soviet Union in the closing stages of the second World War and have been a source of contention ever since.The Soviet Union declared war on Japan in August 1945 as Tokyo was about to surrender, and the dispute has prevented the two nations from signing a formal peace treaty.Takaichi told reporters in Tokyo that the islands, which are just off Hokkaido, were “both historically and under international law” a part of Japan and called the visit by the Russian leader “incompatible with Japan’s consistent position” on the territory.Japanese television showed footage of Putin on the island of Etorofu, or Iturup in Russian, visiting a hospital, meeting residents and trying caviar at a processing plant.About 17,000 Japanese formerly lived on the islands, which today are occupied by about 20,000 Russian citizens.As well as its strategic significance, the island chain – consisting of Etorofu, Kunashiri, Shikotan and the Habomai islet group – provides access to rich fishing grounds and valuable mineral deposits.On Wednesday, Putin travelled to the nearby Russian island of Sakhalin, where he inspected navy drills and declared that the four disputed islands were recognised as Russian in international documents.Shinzo Abe, the late Japanese prime minister, had reached an entente with Putin over the territory, with visits by Japanese citizens to family graves resuming and talk of a future peace treaty. However, Russia’s 2022 invasion of Ukraine prompted Japan to impose sanctions on personnel and entities linked to Moscow, souring bilateral relations.The Russian president acknowledged Abe’s actions in his remarks on Wednesday and went to call the recent sanctions “unprovoked”. He said: “Japan has identified Russia as a major source of threats. I would like to point out that we are not threatening Japan. On the contrary, it has territorial claims against our country.”Though it is Putin’s first visit to the islands, Dmitry Medvedev went to Kunashiri in 2010 when he was president. Medvedev was widely seen as loyal to Putin, who was prime minister at the time. – Reuters