The Soviet Union and Japan, trying to end four decades of conflict over Moscow's occupation of an island group off northern Japan, failed to make progress in talks Monday but agreed to further discussions as a precursor to a peace treaty. Soviet Foreign Minister Eduard Shevardnadze and his Japanese counterpart, Sosuke Uno, met for six hours and 20 minutes Monday on a wide range of bilateral and international issues but ran into a roadblock on four islands in the Kuril group, Japanese officials said. Although the Asia-Pacific neighbors normalized relations in 1956, they never signed a peace treaty to formally end World War II hostilities, which has severely limited the scope of their political and economic relationship. Shevardnadze, on the second day of a four-day visit to Japan, told Uno that Moscow is anxious to improve ties with Japan and hopes to open "a new chapter" in bilateral relations, the Japanese officials said.