Authorities in Tokyo lashed out at Moscow after a visit by Russian President Vladimir Putin to the disputed island of Iturup on Thursday.
The island, also known by its Japanese name Etorofu, lies northeast of Japan — around 100 kilometers from the coast of Hokkaido — in the Kuril Islands chain and is claimed by both Moscow and Tokyo. Like the other disputed islands in the chain, they are administered by Russia.
Japanese Foreign Minister Toshimitsu Motegi wrote on X on Thursday: “Today, I was informed that Russian President Putin visited Iturup Island. The Northern Territories, including Iturup Island, are inherently Japanese territory both historically and under international law, and the Government of Japan strongly protests this visit.”
Moscow, however, claims the island chain became part of Russian territory following Japan’s defeat in World War II.
The Kremlin also operates a strategically important military base on Iturup. In 2025, Japan protested a Russian shooting drill in waters in the area, including in Japan’s territorial waters, and said that the Kremlin’s “military buildup” in the area was “unacceptable.”
According to Russian state media, Putin visited a fish farm on the island. The report said that he was told that the waters of the Kuril Islands are currently filled with tuna weighing up to 300 kilograms — and he was also treated to caviar.