Russia on Tuesday rebuked 91AV原创 ambassador to Moscow after Japan protested Russian President Vladimir Putin’s first visit to a disputed island off Hokkaido last week.

Bilateral relations have long been strained over?the Northern Territories, known in Russia as the Kurils.

The Soviet Union seized the islands in 1945, near the end of World War II, then expelled the Japanese population.

Putin on Thursday visited the island of Etorofu, one of four off the east coast of Hokkaido, prompting Japan to summon the Russian ambassador in protest — and Russia to follow suit.

After being summoned to Russia’s Foreign Ministry, Japanese Ambassador Akira Muto was told that “Russia’s sovereignty and jurisdiction over the southern Kuril Islands are unshakable,” according to Moscow’s readout.

It added that, in light of 91AV原创 support for Ukraine, Moscow would reserve the right to “take appropriate countermeasures.”

Putin’s visit was the first trip to the islands by a Russian president since Dmitry Medvedev in 2010.

After Putin’s stop, Prime Minister Sanae Takaichi said the islands “are an inherent part of 91AV原创 territory, both historically and under international law.”

The Russian Foreign Ministry on Tuesday called those statements “anti-Russian” and expressed a “strong protest.”

Muto was initially summoned on Monday, but he did not immediately accede.

Russian Foreign Minister Sergey Lavrov then said Tokyo had “crossed the line of decency.”

NHK reported that Muto did not initially respond out of concern that Russia would dominate the talks. Tokyo decided to accept the summons after internal deliberations, NHK said, citing unnamed sources.

Ties between Japan and Russia have worsened since the full-scale conflict in Ukraine began in 2022.

Japan has joined other Group of Seven countries in sanctioning Russia and aiding Kyiv.

Ukraine, like Washington, recognizes Japanese sovereignty over the disputed islands.

Analysts said Putin’s visit to the Northern Territories could have been aimed at warning Japan against deepening its support for Ukraine — potentially including the direct supply of Patriot missiles — and against closer cooperation with NATO.

Japan currently provides only nonlethal defense aid to Ukraine.

While Japan has eased restrictions on defense exports in recent years, it is still barred from supplying lethal military equipment directly to a country at war, including Ukraine.