Russian President Dmitry Medvedev's visit Monday to Kunashiri Island, one of the Russian-held islands claimed by Japan, has some Japanese analysts concerned that territorial talks between the two are likely to stall for a significant period.

"The difference between the stances of Japan and Russia is becoming pronounced, so the territorial talks are likely to encounter difficulty," said Toshihiko Ueno, a Russia expert at Sophia University in Tokyo. "Russia may continue to argue that there is no significant problem about the status quo unless Japan advances proposals such as joint development of the disputed territories."

"Japan's contention that its Northern Territories (Russian-held islands) are held illegally by Russia is perceived by the Russians to have gained more traction under the government led by the Democratic Party of Japan, so Russia apparently is insisting on its sovereignty over the islands, to stress that it is not going to change its interpretation of World War II," Ueno added.