Moscow — The Soviet Union, chortling over recent strains in US-Japanese relations, is moving to patch up its own battered ties with that East Asian neighbor. An early, radical improvement in Soviet-Japanese relations seems virtually impossible. Both publicly and privately the Soviets are still adamantly opposing any compromise on what Japanese officials see as the most pressing issue in their ties with Moscow.
This is the "northern territories" question: the future of the disputed Kurile Islands off Japan's northern shore, occupied by the Soviet Union since World War II and now home for an estimated 7,000 to 10,000 Soviet troops.
But Moscow seems to hope that Japan can be convinced to put the territories issue aside for now and join in a gradual, piecemeal improvement of relations.
This, in Soviet eyes, could begin on the economic front, where trade has suffered in the wake of the Soviet invasion of Afghanistan. The Soviets would like Japanese cooperation in developing remote, resource-rich Siberia, Japanese sources here say.
And what about the Kurile Islands? "If you are driving and find a big stone in the middle of the road," remarked a member of Moscow's foreign policy establishment to this reporter, "you do not ram into it . . . but try instead to find a way around it."
Since early this year, the Soviets seem to have been making a concerted effort to do just that.
The campaign, foreign diplomats here suggest, is likely to take on added momentum amid signs of strain in Japan's ties with the United States.
The official Soviet news media have gleefully reported recent incidents seen as complicating the US-Japanese relationship: the accidental sinking of a Japanese boat by an American submarine; the spat over use of the word "alliance" at the recent Japanese-US summit talks in Washington; the cutting short of joint naval exercises in the Sea of Japan; and, most recently, reports that visiting US ships have long been toting nuclear weapons in Japanese waters.
When Washington said May 20 that a "scheduling difficulty" was prompting Secretary of State Alexander M. Haig Jr. to cancel a visit to japan, the official Soviet news agency termed this a mere "diplomatic trick designed to camouflage the political essence of the problem" in Japanese-US ties.
There have been increased Soviet-Japanese contacts in recent months, following Soviet President Leonid Brezhnev's public call in February for an improvement in ties with Tokyo.
Among recent Soviet visitors to Japan are a trade delegation, prominent foreign-policy journalist Alexander Bovin of the government newspaper Izvestia, and Valentina Tereshkova, member of the Communist Party Central Committee and chairman of the Soviet Women's Committee.
A delegation of Japan's ruling Liberal Democratic Party, including a former Japanese foreign minister, met with Soviet officials here in April. So did the president of Japan's federation of economic organizations, Tokyo news reports said.
At the end of April, Japan's ambassador here conferred with Soviet Foreign Minister Andrei Gromyko. In May, Soviet officials met visiting members of the Japanese Buddhist organization Soka Gakkai.
Sparring over the territories issue is said to have complicated the official contacts. The Soviets argue privately that a compromise over the islands would imperil this nation's security and perhaps set a precedent for territorial claims against the Soviet Union.
Meanwhile, a fresh five-year trade accord with Japan has been signed in Moscow. Soviet officials told the visiting Liberal Democratic group they were ready also to extend the countries' joint fishing accord, which expires next year. And the Soviets offered to resume talks on Japanese fishing access to waters near the southern Kurile Islands.
Now, Deputy Soviet Foreign Trade Minister Ivan Grishin suggested to the visitors, it would be wise to remove further "artificial barriers" to more trade.
Soviet officials are also stressing the seriousness of proposals made by Mr. Brezhnev in February to agree on military "confidence-building measures," including advance not ification of troop exercises, for Asia.