President Mikhail Gorbachev stopped in a Soviet Far East city during an unprecedented trip to Tokyo and placed a wreath at a memorial to Japanese who died in Siberian prison camps during the Stalin era.

Gorbachev left behind an unresolved 6-week-old coal miners' strike, the threat of a renewed strike by workers in the Byelorussian capital of Minsk, growing demands for his resignation by both rightist and leftist politicians, and an economy lurching toward bankruptcy.On a stopover in Khabarovsk, he laid a wreath at a memorial to Japanese prisoners of war who died in Siberian prison camps during Josef Stalin's regime.

For its part, the Japanese government prepared to release $100 million in humanitarian food aid that it had suspended in January when the Soviets cracked down on Baltic independence movements, Japanese press reports said.

In addition, Japan will donate 38 tons of medical supplies for Soviet victims of the 1986 Chernobyl nuclear power plant disaster.

Gorbachev planned to spend two days in Khabarovsk, a city of 591,000 people, before flying to Tokyo for what Soviet newspapers have called the possible real estate deal of the century with Japan over the Kuriles, four small islands the Red Army seized from the Japanese near the end of World War II.

It will be the first visit to Japan by a Soviet leader.

Soviet newspapers have said Gorbachev might return the islands to Japan in a deal for $26 billion. In a bizarre incident this spring, Gorbachev at one point prepared to bring a suit against Artem Tarasov, a Russian republic lawmaker and cooperative millionaire, for saying in a public forum that Gorbachev would dispose of the island for such a sum.

The dispute over ownership of the Kuriles, which the Japanese call their Northern Territories, has chilled relations between the two countries and has not been off the pages of Soviet newspapers for a month in the run-up to Gorbachev's trip.

Although Gorbachev has never said that the Soviets would return the Kuriles, which stretch northeast from Japan's northernmost island of Hokaido, he said last week it benefited nobody that Moscow and Tokyo should be estranged.

No Soviet leader or Russian czar has ever made a state visit to Japan, although Boris Yeltsin, head of the Russian republic, largest of the 15 Soviet republics, went there last year.

Gorbachev will spend four days in Japan meeting with Prime Minister Toshiki Kaifu and other officials, and will end his trip with a stopover on the South Korean island of Cheju-do on April 19 where he will meet briefly with South Korean President Roh Tae Woo.