The Japanese government plans to consider countermeasures against Russian President Vladimir Putin's visit to one of the four islands that are controlled by Russia and claimed by Japan.

Axar.az reports, citing Japan Broadcasting Corporation, that one possible measure is strengthening existing sanctions that Tokyo has already imposed on Moscow, in tandem with the international community, for Russia's invasion of Ukraine.

The islands are called the Northern Territories in Japan. The Japanese government maintains the islands are an inherent part of Japan's territory. It says the islands were illegally occupied after World War Two.

Japanese Prime Minister Takaichi Sanae on Thursday addressed Putin's trip to Etorofu, one of the islands. She underscored that the islands "are an inherent territory of Japan in light of historical facts and based on international law."

Japanese Foreign Minister Motegi Toshimitsu summoned the Russian Ambassador to Japan, Nikolay Nozdrev, to the Foreign Ministry in Tokyo.