I would like to correct a few of the inaccuracies in the article by Kenneth Adelman ["Pulling Japan Into the Big Leagues," op-ed, March 27].

Adelman talks about Japan's scooping up Iranian oil and aiding the Iranians to skirt a U.S. freeze of their assets last year. The fact is that the purchase by some private Japanese companies of Iranian oil at high spotprices was made to cover shortfalls arising from a substantial reduction in oil supplies from major international oil companies to the non-affiliates in Japan.

The Japanese government discouraged these private firms from buying oil at unduly high prices and asked them to take corrective measures regarding oil already purchased. Furthermore, there is no substance whatever to Adelman's allegation that Japanese banks cooperated with the Iranians to skirt the U.S. freeze on Iranian assets. The Japanese government, moreover, had advised the deputy secretary of the Treasury, Robert Carswell, last December that it will keep in step with European countries as regards its economic and financial relations with Iran.

Adelman conveys the impression that Japan is only intent on making an accommodation with the Soviet Union. This is patently untrue. Immediately after the Soviet invasion of Afghanistan, the Japanese government issued a statement on Dec. 29, 1979, in which it said the Soviet invasion is contrary to international justice and harmful to international peace and security; it strongly urged the Soviet Union to cease its armed intervention in Afghanistan immediately.

In his policy statement before the Japanese Diet on Jan. 25, 1980, Prime Minister Masayoshi Ohira further stated in reference to the Afghan problem, that we would, on the basis of our solidarity with the United States and in cooperation with other friendly countries in Europe and elsewhere, study and implement appropriate measures including tightening of export controls through the Coordination Committee for Export Controls, even if these measures involve sacrifice on our part. Some high-level exchanges of personnel with the Soviet Union were suspended or postponed. As regards the Moscow Olympics, the Japanese government made known its position on Feb. 1, that while the decision to participate or not rests with the Japan Olympic Committee, the Olympics must be held in a peaceful climate.

Furthermore, the Japanese Diet recently passed resolutions condemning the Soviet armed intervention in Afghanistan as well as the Soviet military buildup in the Japanese northern territories occupied by the Soviet Union since 1945.

Such a series of steps by Japan is far from constituting "downright accommodation," as alleged by Adelman.

In regard to Japan's defense expenditures, Adelman focuses on these expenditures' being 0.9 percent of GNP and argues that their projected increase will be "microscopic." He omits mentioning, however, that given a GNP of about $1 trillion in 1979, Japan's military spending is already ranked eighth in the world. Furthermore, it is not justifiable to compare this percentage with that of other countries, particularly NATO countries, because their defense expenditures are calculated on a different basis than are those of Japan.

Adelman demands that "Japan should assume more than its current half of the $1.2 billion doled out annually for U.S. forces stationed on its islands." He is misinformed. Secretary of Defense Harold Brown pointed out in his annual report (FY 1981) that "Japan provided about $1 billion in FY 1979 to help offset the cost of this deployment."

As Foreign Minister Saburo Okita stated in the course of his visit to Washington two weeks ago, Japan will continue to make every effort to increase its defense expenditures steadily despite the severe fiscal circumstances that it faces.

The Japanese government is planning to purchase 200,000 to 300,000 tons of surplus U.S. grain and give part of it as grant assistance to developing countries.

Japan is already providing substantial aid to countries of increasing importance to the Western countries, such as Pakistan and Egypt. It has stated its intention to extend economic assistance in 1980 of $128 million (2.2 times the amount of last year) to Pakistan, and also recently pledged $128 million to Egypt. With respect to Turkey, assistance and export credits in 1979 amounted to $70 million, not zero, as alleged by Adelman, and we are considering an appropriate level of assistance for this year as well.

Adelman's article, unfortunately, can only contribute to misinformation and misunderstanding about Japan and U.S.-Japanese relations. We welcome constructive suggestions on Japan from Americans. But I do hope that when such suggestions are made, they are based on accurate information.