TOKYO -- Prime Minister Toshiki Kaifu and President Mikhail S. Gorbachev gave top priority to their countries' toughest territorial dispute yesterday in the opening sessions of the Soviet leader's historic summit visit.
The two leaders sealed the lips of all in the room, then tried for an hour and a half -- about half of their first meeting -- to find a last-minute way out of the dispute that has for four decades confounded all attempts to draft a peace treaty legally ending the two Sea of Japan neighbors' World War II state of belligerence. The dispute centers on four tiny, flinty islands in the Kuril chain that the Soviets took over as the Japanese were surrendering.
A Japanese briefer described the afternoon's talks as "frank," and a Soviet briefer said they were "candid"-- diplomatic terms usually reserved for blunt disagreements over thorny issues.
Mr. Gorbachev hopes the four-day summit will produce enough progress in long-stunted Japan-Soviet relations to begin to draw in large-scale Japanese investment that is badly needed to help reignite the sputtering Soviet economy.
But the Japanese government is determined not to facilitate private investment on that scale before the two neighbors find a formula to resolve their territorial dispute.
Japanese newspapers have reported for more than a week that Japan is prepared to organize up to $28 billion in private investment and soft credits if there is a breakthrough on the islands issue.
Mr. Gorbachev and Mr. Kaifu are likely to take up the territorial issue again this morning during the second of three planned sessions and agreed that a fourth session might be useful, a Japanese Foreign Ministry official said. The official, who was present for the three-hour meeting, briefed foreign correspondents at the Foreign Ministry, speaking on condition that he not be named.
The two leaders specifically ordered that anything more than a mention of the existence of the peace treaty talks be excluded from the two sides' news briefings, he said.
The two "were open and candid with each other to the maximum extent," Vitaly Ignatenko, Mr. Gorbachev's official spokesman, told reporters at a news conference.
But he, too, said he could not discuss the substance beyond confirming that much of the talk dealt with "the lack of a peace treaty between the two countries."
The Japanese briefer described the talks as "a very frank exchange of views" but said that the atmosphere was "friendly" and that most statements were delivered "in a matter-of-fact manner."
The three-hour afternoon session was the meat of the opening day of the first-ever visit to Tokyo by any top leader of a country that has shared recurring difficulties with Japan since before 1904, when the two neighbors fought the first war in which an Asian country ever defeated a Western power.
It also dealt with a broad range of other issues in Japan-Soviet relations, including 15 documents now being prepared for the two leaders to sign. The documents deal with such secondary matters as Japanese plans to provide technical help for Soviet economic reform, air transit rights, fishing waters along their borders, trade and cultural exchanges.
Mr. Gorbachev has infused his visit with symbolism intended to help put to rest the two countries' long history of difficult relations.
He brought with him a list of names of more than 55,000 Japanese who died in harsh, Stalinist labor camps in Siberia, where about 600,000 Japanese soldiers were interned after World War II.
Yesterday he and his wife, Raisa, met three times with Emperor Akihito and Empress Michiko, including a meeting at a state banquet at which the emperor presided.
"It is my earnest hope that your excellency's current visit will mark a historic turning point in establishing truly stable ties of friendship between our two countries," the emperor said in his toast opening the black-tie banquet.