TOKYO: Japan said Friday it had protested against Russia's notification that Moscow would conduct missile tests off disputed islands visited by President Vladimir Putin earlier this month.
"We lodged a protest in response to the notification about the plan to conduct a missile test" off the Kuril islands, known as the Northern Territories by Japan, a Japanese government spokesman told AFP.
Japanese news agency Kyodo quoted Russia's Pacific Fleet as saying that it had already conducted the missile test, although it was unclear when it took place.
The Russian naval fleet said a unit equipped with the Bastion surface-to-ship missile system conducted the test, Kyodo reported.
The guided missile cruiser Varyag, the flagship of the Pacific Fleet, also took part in the test, along with the Omsk nuclear-powered submarine, the news agency said.
The exercise simulated an attack on enemy vessels and succeeded in hitting all the intended targets at a range of at least 300 kilometres (186 miles), the fleet added, according to Kyodo.
"We believe Russia's military buildup in the Northern Territories including these missile drills runs counter to Japan's position regarding the Northern Territories, and is unacceptable," Foreign Minister Toshimitsu Motegi told reporters Thursday during a trip to Oman.
Putin made his first official visit to the islands, administered by Russia since 1945, on August 13, prompting Japan to summon Russia's ambassador -- a move then reciprocated by Moscow.
Putin went there after visiting the nearby Russian island of Sakhalin, where Russia's navy was conducting drills.
His visit was the first trip to the islands by a Russian president since Dmitry Medvedev in 2010.
After Putin's stop, Japanese Prime Minister Sanae Takaichi said the islands "are an inherent part of Japan's territory, both historically and under international law".
Ties between Japan and Russia have worsened since the full-scale conflict in Ukraine began in 2022.
Japan has joined other G7 countries in sanctioning Moscow and aiding Kyiv.
Ukraine, like the United States, recognises Japanese sovereignty over the disputed islands.
Analysts said Putin's visit to the Kurils 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 non-lethal defence aid to Ukraine.
While Japan has eased restrictions on defence exports in recent years, it is still barred from supplying lethal military equipment directly to a country at war.