Amid the noisy rumblings of Kremlin disapproval, Japan pressed its claim to four Soviet held islands today with parades, rallies, song, promotional gimmicks and a strong official blessing.

It was the first government-proclaimed "Northern Territories Day" and downtown Tokyo echoed with chants demanding the return of the islands, held by the Soviet Union since the end of World War II.

The government's involvement reflected its growing irritation with Soviet military moves on the islands, just a few miles off Hokkaido, and a desire to take a tougher public posture on an issue with strong emotional appeal for many Japanese.

In Tokyo, Prime Minister Zenko Suzuki lent his support in a rally where he declared that the Soviet retention of the islands "is to be deeply regretted." He called for "peaceful negotiations" to get them back, something the Soviets flatly reject.

There were official rallies in three other cities. The Japanee tobacco monopoly sold special packs of cigarettes commemorating Northern Territories Day and a girls' choir opened the Tokyo rally with a song, "Spring Shall Come Again," lamenting the Soviet control. More than 90 private groups joined in the commemoration.

The Soviet Union this week attacked the event in advance with several shrill propaganda blasts contending that it marked another stage in the revival of Japan's "militarism."

By officially endorsing the rallies, the Japanese government was making "anti-Sovietism a state policy," declared Tass, the official Soviet press agency. Izvestia, the government newspaper, labeled the event "a nationwide provocative show."

The four islands, northeast of Hokkaido, Japan's second-largest island, were seized by Soviet forces after World War II. Japan has pleaded ever since for their return and for a while the Kremlin talked of negotiations on their future, but it now claims they are not subject to negotiation.

While insisting that they are Japanese territory, the government here has been unable to do anything more about the islands. For a while, Tokyo appeared to be playing down the issue to avoid harming relations with Moscow. Japan does a booming trade with the Soviets, and many businesses are eager to keep relations smooth.

On the other hand, some private groups have charged the government with complacency and urged it to take a bolder public stand in favor of return. It was partly to satisfy those groups that the government proclaimed this day of commemoration.

Soviet moves to militarize the islands also have angered Tokyo. More than a division of Soviet troops are stationed on one of them.

The Soviet invasion of Afghanistan added to a growing mood of nervousness here about Kremlin intentions and Japanese-Soviet relations were further cooled when Japan boycotted the Moscow Olympics and enforced economic sanctions.

Against that background, the islands issue became more significant and private groups seeking return stepped up their campaign last year, calling on the government for more public support. A nationwide petition campaign has gathered more than 18 million signatures and the support of more than 1,600 villages, towns and cities.

Feb. 7 was picked for the commemoration because on this day in 1855 Japan and czarist Russia signed a treaty of commerce and friendship that confirmed Japan's claims to the four islands.

The event brought out many noisy members of Japan's right-wing organizations, who paraded through Tokyo behind sound trucks blaring demands. About 600 of them gathered in a Tokyo park and ended their rally by bowing toward the Imperial Palace and then marching to the Soviet Embassy.

The popularity of the campaign, however, drew out leftist politicans as well. Representatives of the Socialist and Communist parties attended the rally where Suzuki spoke.

On Hokkaido, about 2,000 people held a rally at Nemuro, a fishing port from which the four disputed islands are visible.

Earlier in the week, a Soviet patrol boat had suddenly appeared off Nemuro, apparently to emphasize the Soviet disapproval of the rallies. It was still anchored there yesterday.