There is a growing perception in Japan that more political muscle is needed if this country is to be taken seriously by the Soviet Union. It has long been said that, on the international scene, Japan is an economic giant but a political dwarf. This perception is becoming more common in foreign policy making circles here, stemming in part from frustration at the lack of progress in thawing out frigid Japan-Soviet relations.
Working-level discussions in Tokyo earlier this month between Foreign Ministry officials of the two countries revealed no early prospect of narrowing the political breach between Tokyo and Moscow.
This prompted the Japanese ambassador in Moscow, Masao Takashima, home briefly for consultations, to suggest that the only answer is to build up more political muscle.
Japan should strengthen relations with the United States and neighboring countries in Asia - specifically China, South Korea, and members of the Association of Southeast Asian Nations - so as to boost its political position in Asia, Ambassador Takashima said in an interview.
This would help create an atmosphere in which the Soviets could not possibly ignore Japan in their own policy toward the region. ''The Soviet Union will follow a foreign policy appropriate to the political climate in Asia once such an atmosphere has been created,'' the ambassador said.
But while the envoy supported the Japanese government's determination to take a strong line with Moscow on key issues - particularly the longstanding ''northern territories'' dispute - he also stressed the need to maintain political dialogue and promote cultural and personal exchanges ''to avoid Soviet misunderstanding of Japanese foreign policy.'' In that sense, despite the apparent lack of progress, the recent Tokyo working-level talks had been extremely useful, Mr. Takashima added.
Soviet Vice-Foreign Minister Mikhail Kapitsa led Moscow's delegation to the two-day consultations, the third round of talks since 1979. The Japanese delegation was led by Deputy Foreign Minister Toshijiro Nakajima. Mr. Kapitsa also had a long meeting with Foreign Minister Shintaro Abe.
From these encounters a clear picture emerged of current Japanese thinking on improving bilateral relations.
Three preconditions have been laid down: that bilateral ties be developed on the basis of a 1973 agreement for handling ''pending issues''; that there should be a complete withdrawal of military forces from Soviet-held islands east of Hokkaido which Japan wants back; and Soviet Foreign Minister Andrei Gromyko should visit Japan to resume talks on a peace treaty.
The Japanese are clinging to their interpretation of a joint 1973 communique, issued when then Prime Minister Kakuei Tanaka met the late President Leonid Brezhnev in Moscow, which referred to ''unsettled problems since the end of World War II.'' Tokyo says this refers to the return of the ''northern territories''; Moscow has consistently maintained that no territorial problem remains.
And the latest round of talks in Tokyo indicated no narrowing of the perception gap.
A Soviet military buildup on the southern Kurile Islands, which are virtually within sight of Japanese territory, is coupled with a threatened buildup of SS- 20 medium-range missiles in the Soviet Far East. These missiles are aimed at Japan and have heightened Japanese concern.
A visit to Tokyo by Mr. Gromyko has been pending for more than four years, but Mr. Kapitsa stressed it would be inappropriate now in view of the ''existing atmosphere,'' which includes Japan's apparently growing military ties with the US.
He repeated Soviet desires for a peace treaty but said that if Japan was not ready for such a step, a good neighbor treaty in its place and more Japanese technological and economic cooperation in the development of Siberian natural resources would be helpful.
Japanese Foreign Ministry sources, however, say that stable relations must precede long-range economic cooperation.
This was apparently a hint aimed at sections of the business community eager to step up flagging trade and economic cooperation with the Soviets regardless of current political developments, in the belief this will contribute to greater Tokyo-Moscow harmony.
Japanese officials agree that relations between the two countries are at their lowest ebb in three decades. But they say the ball is firmly in Moscow's court.
The recurrent message is: Return the northern territories to Japan, stop threatening us with your nuclear missiles, and we can start laying foundations for a friendlier relationship.
The Foreign Ministry assessment, however, is that the Soviet Union's main strategy now is to continue trying to drive a wedge between Japan and the United States and to separate Japan from the US defense orbit.
This may be accomplished in part by giving encouragement to such groups as the antinuclear protesters anxious about the hawkish defense stance of Prime Minister Yasuhiro Nakasone. The Soviets also like to remind Japan's neighbors of the lessons of World War II and that a rearmed Japan could once again be a threat to East Asia.