MOSCOW (AP) — Russian President Vladimir Putin on Thursday made his first visit to the Kuril Islands, a Moscow-controlled Pacific archipelago that also is claimed by Japan, which voiced a diplomatic protest over the trip.

Putin visited a fish plant, a hospital and a school on Iturup, one of the volcanic chain's southern islands. He also briefly spoke to local residents and met with the governor of Russia's Sakhalin region, Valery Limarenko.

Japan asserts territorial rights to the four southernmost islands of the chain, which it calls the Northern Territories. The Soviet Union took them from Japan in the final days of World War II, and the dispute kept the countries from signing a peace treaty formally ending their hostilities.

Decades of diplomatic efforts to negotiate a settlement haven’t produced any visible results. Moscow over the years has also bolstered its military presence on the Kurils in moves that appeared to underscore its firm stance in the dispute.

Japanese Foreign Minister Toshimitsu Motegi said his country “strongly protests” Putin's visit to Iturup, which Japan calls Etorofu.

“The Northern Territories, including Etorofu (Iturup) Island, are Japan’s inherent territory both historically and from the perspective of international law,” Motegi said in a statement.

He summoned Russian Ambassador Nikolay Nozdrev to the ministry in Tokyo and lodged a strong protest over the visit, requesting that he "promptly report the message back to Moscow,” the minister told reporters afterward.

Japan also protested in 2021 when Russian Prime Minister Mikhail Mishustin visited Iturup.

Putin in recent days has visited several regions in Siberia and the Far East. Before coming to Iturup, he stopped on Sakhalin Island to attend the final part of drills by Russia's Pacific Fleet.

Speaking aboard a warship that was participating in the naval exercises, Putin said Wednesday that the current status of the Kuril Islands “is enshrined in international documents as a reality that arose following the outcome of the World War II.”

“But even here, Russia was prepared to seek a solution with the goal of concluding a peace treaty with Japan,” he said.

Putin said that in the past, Moscow “had developed constructive relations with a number of Japanese leaders, including the tragically deceased former Prime Minister Shinzo Abe, who did much to bring Japan and Russia closer together, to align our positions.”

Japan imposed sanctions on Russia after it sent troops into Ukraine in February 2022 and “listed Russia as a source of primary threats,” a change in that constructive relationship, he added.

Russia remains ready “to cooperate with all its neighbors, including Japan and other states in the region,” Putin said.

Japan’s Prime Minister Sanae Takaichi said Putin’s visit is “incompatible with the Japanese position on the Northern Territories” and is “absolutely unacceptable.”

She said the visit was a further blow to the already-strained ties between the two countries over Ukraine, and that Moscow should understand the consequences.

“We must say this visit has further hardened Japanese public sentiment toward Russia and has made it more difficult to restore bilateral relations in the medium to long term,” she said. “We hope the Russian side fully understands the seriousness of this.”

One of the reasons Japan has made the effort to maintain ties with Russia is to allow former Japanese residents to return to the islands and pay tribute at their graves as a humanitarian consideration.

Dmitry Medvedev, Russia's former president and prime minister who now serves as deputy chair of the country's Security Council, responded to Takaichi's remarks on X by saying, “This chatter won't change a thing.”

The Kuril Islands “were, are, and will remain Russian land,” Medvedev, who himself visited the Kuril Islands four times as president and prime minister, wrote. “Anyone who fails to understand this will face the monstrous consequences of their delusion.”

——

Associated Press writer Mari Yamaguchi in Tokyo contributed.

Copyright 2026 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed without permission.