Prime Minister Ryutaro Hashimoto will fish, take a stroll, enjoy a sauna and indulge in good food in Siberia with Russian President Boris Yeltsin this weekend in a bid to warm up bilateral relations.

Hashimoto will try to improve his personal relationship with Yeltsin during the two-day visit under the theory that deepened understanding between the two leaders will eventually lead to resolving the long-standing territorial issue, according to the Foreign Ministry.

"The summit is an informal one and its main purpose is to improve the two leaders' personal friendship," a ministry official said. The summit in Krasnoyarsk, eastern Siberia, will be unprecedented in style.

Hashimoto and Yeltsin will not sit down in a room for a fixed agenda; they will freely discuss bilateral and international issues as they engage in casual activities together. "A breakthrough in the territorial issue could be achieved sometime in the future based on a strengthened personal relationship," another official said. "Therefore, no dramatic improvement in the territorial issue will be achieved in this summit," he added.

The dispute over three islands and a group of islets off Hokkaido has prevented Japan from signing a peace treaty to formally declare an end to World War II hostilities with Russia. Under dispute are Etorofu, Kunashiri, Shikotan and the Habomai islets.

The two leaders are expected to discuss ways to increase Japanese investment in Russia. They will also discuss bilateral economic cooperation to develop energy resources such as petroleum and natural gas in the Russian Far East.