A visit this month by Japanese to the Russian-held islands off Hokkaido under a visa-free exchange program has been canceled due to Russia's request for the submission of certain travel documents, sources said.

The documents, which Russia says have become necessary due to legal changes, include applications by foreigners for the registration of visits when former Japanese residents of the islands stay there for more than seven hours a day, as well as embarkation cards.

It is extremely rare for the exchange program with Russian islanders to be suspended due to reasons other than bad weather. The move is viewed as a sign of Russian displeasure with Japan, which has followed the United States and European nations in imposing sanctions on Moscow after its annexation of Crimea last year.