Japan watches Russian military near disputed isles

TOKYO (Reuters) - Japan is closely monitoring stepped-up activity by Russia's military near disputed islands, Japan's chief spokesman said Thursday after Moscow said it would deploy new weapons to the area.

Relations between Japan and Russia have been clouded by a long-running dispute over the four islands, called the Southern Kuriles in Russia and the Northern Territories in Japan.

The former Soviet Union occupied the islands off northern Japan at the end of World War Two and the row has weighed on bilateral ties since, preventing the two countries from signing a formal peace treaty despite growing economic ties.

Japan is also embroiled in a territorial dispute with China and the government's handling of the spats has been heavily criticized at home, adding to a fall in Prime Minister Naoto Kan's support ratings.

"Russian military activity near our country is increasing and we will continue to monitor this closely with interest," Chief Cabinet Secretary Yukio Edano told a news conference.

"We would like to deal with this based on the stance that the four islands are Japan's territory and that we want to resolve the territorial issue and sign a peace treaty in accordance with existing agreements and statements."

Russian President Dmitry Medvedev, who infuriated Japan in November by making the first visit by a Russian leader to one of the islands, said Wednesday that Russia should deploy modern weaponry to ensure the security of the islands.

Medvedev's comments were in line with a recent strengthening in rhetoric over the disputed islands aimed at fuelling nationalism in Russia, said professor Shigeki Hakamada, an expert on Russia at Aoyama Gakuin University in Tokyo.

"Japan has been saying it wants to discuss both economic cooperation and signing a peace treaty," he said.

"But in recent years, since (Prime Minister Vladimir) Putin (became president), there has been no progress in talks on a peace treaty ... Japan is frustrated with this."

Japanese Foreign Minister Seiji Maehara will visit Russia from Friday for talks with his counterpart, in which the islands will likely be a focus.

Maehara reiterated Japan's position ahead of the visit.

"Looking at it from an international law perspective, the Northern Territories are Japan's inherent territory," he told a separate news conference.

"Russia's occupation of them are groundless based on international laws."

(Reporting by Chisa Fujioka and Yoko Kubota; Editing by Michael Watson)