Former residents of Russian-held islands have attended a rally to demand the islands' early return to Japan, which calls them the Northern Territories.

About 750 former islanders, relatives and others gathered at the annual rally held in Nemuro City in the northern Japanese prefecture of Hokkaido on Friday.

The Japanese government has designated February 7 as Northern Territories Day. On the day in 1855, Japan and Russia signed a treaty that says the four islands are Japanese territories.

Russia controls the islands. Japan claims them. 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.

At Friday's event, 85-year-old Kudo Shigeshi, who was a resident of the Habomai Islands, expressed the former residents' resolve in a speech. He said this year marks 80 years since they were forced to leave the islands by the then Soviet Union.

He pointed out that visits to their ancestors' graves on the islands had been conducted on a humanitarian basis, but have now been suspended. He said he is worried about the outlook for the islands, but that he will do his utmost using his remaining strength until they are returned.

The participants then chanted slogans, one meaning "Russia must return the islands."

The grave visits and a visa-free exchange program involving former islanders have been suspended mainly because of Russia's invasion of Ukraine. There is no prospect for their resumption.

The average age of the former residents is 89. Solving the issue can be called a race against time.

Tsunoka Yasuji, an 87-year-old former Habomai resident, said he hopes the grave visits will be resumed so he can offer incense at one on his home island.