Japanese Prime Minister Junichiro Koizumi said Friday he plans to visit Russia on May 9 to attend a 60th anniversary ceremony of the World War II Allied victory over Nazi Germany. ''I'm considering attending the ceremony,'' Koizumi told reporters in Tokyo. The Japanese prime minister said that while each country had its own war experiences, the ceremony was aimed at demonstrating that enemies have since become friends. World leaders including German Chancellor Gerhard Schroeder, U.S. President George W. Bush and South Korean President Roh Moo Hyun are expected to attend the event to mark what Moscow calls the 60th Anniversary of Victory in the Great Patriotic War. Russian President Vladimir Putin is expected to visit Japan later this year to discuss disputed territorial issues. Japan wants Russia to return four islands claimed by Tokyo. The islands, located off Japan's northernmost prefecture of Hokkaido, were occupied by Soviet forces at the end of World War II. Japan wants to resolve the dispute before concluding a World War II peace treaty with Russia by making clear that the disputed islands - Kunashiri, Etorofu, Shikotan, and the Habomai islet group - belong to Japan, while being flexible about how they are actually returned. Russian Foreign Minister Sergei Lavrov will visit Japan from May 30-31 to lay the groundwork for Putin's visit later this year. Speaking about bilateral relations, Koizumi said, ''I would like to take the Japan-Russia relations in a direction where we can increase exchanges and foster a relationship of trust in order to solve the Northern Territory issue and conclude a peace treaty.''