Russia's military says Russian planes flew in the region of joint U.S.-Japan military drills in the Pacific Ocean but did not violate airspace rules.
Interfax news agency quotes Roman Martov, a spokesman for Russia's Pacific Ocean Fleet, as saying the planes "carried out their planned flights in the region of regular activity of [Russia's] fleet."
Japan's "Sankei" newspaper reports that Russian patrol planes entered airspace above the Sea of Japan this week, causing a partial halt to military exercises between the United States and Japan.
The report quotes Japanese Chief Cabinet Secretary Yoshito Sengoku as saying fighter planes from the U.S.-Japan side had been scrambled, but he did not give details.
Ties between Japan and Russia have been strained since Russian President Dmitry Medvedev visited one of four islands claimed by both countries last month.
compiled from Reuters reports