The video, dubbed "G20: Inspiring cities of Japan - Osaka", was initially released on the YouTube account of the office of Japanese Prime Minister Shinzo Abe in February. It came into the spotlight only after being reposted by the summit's website.
The start of the video features a map of Japan, which includes a Japan-disputed group of islands, the Kurils: Iturup, Kunashir, Shikotan and Habomai, depicted as part of the Asian country.
Russian officials have not yet commented on the controversial video.
In June, Russian President Vladimir Putin stressed that Moscow was not planning to lower the Russian flag over the Kurils, despite Japan's territorial claims, stressing that the islands remain part of Russia.
The relationship between Moscow and Tokyo has long been strained, and a peace treaty at the end of World War II was never signed because of Japanese claims to the Kuril islands.
The summit in Osaka did, however, result in the announcement of new joint economic projects on the islands, which may signal a thaw in relations between the countries.
