Tokyo lodged a strong protest Monday over Russian President Dmitry Medvedev's visit the same day to Kunashiri Island, one of the four Russian-held islands off Hokkaido that Japan wants returned.
Foreign Minister Seiji Maehara summoned Russian Ambassador to Japan Mikhail Bely to the ministry later in the day to file an official protest over the president's trip.
During the meeting, Maehara told the ambassador that the president's visit "is in conflict with Japan's principle position and hurts the Japanese public sentiment."