Moscow — Senior officials yesterday gave the strongest indication yet that Moscow's 18-month-old moratorium on nuclear tests will not be renewed on Jan. 1. Most of the 23 nuclear tests carried out by the United States since the Soviets declared their moratorium on Aug. 6, 1985, were designed to develop new ``third generation'' nuclear weapons, not to test existing devices, First Deputy Foreign Minister Yuli Vorontsov told a press conference.
The US is making a ``fairly active effort to achieve military superiority over the Soviet Union,'' he added.
The US's lack of interest in the moratorium, its breaking of the second Strategic Arms Limitation Treaty (SALT II), and the revelations of arms deliveries to Iran are all being depicted by the Kremlin as separate aspects of a single phenomenon: the growing belligerence of the Reagan administration.
Speaking of the lack of US interest in the moratorium, Mr. Vorontsov, who is also a member of the Communist Party Central Committee, said: ``Under these conditions, continuing the Soviet unilateral moratorium indefinitely would mean threatening the security of the Soviet Union and its allies.''
Asked about the chances that the moratorium would be renewed when it expires Jan. 1, Vorontsov replied that ``everything depends on the behavior of the United States administration before Dec. 31.''
Vorontsov and another official, Andronik Petrosyants, chairman of the State Committee for the Utilization of Atomic Energy, both expressed doubt during the press conference that the US would change its position. Mr. Petrosyants quoted US officials as saying that a full ban on nuclear tests was a ``long term'' objective that could only be achieved when nuclear weapons were eliminated.
For Moscow, the essence of the issue is maintaining strategic parity with the US. Soviet achievement of this in the mid-1970s is regularly described here as a turning point in US-Soviet relations and in the Soviet position in the world.
Now, Soviet officials say, far from being interested in nuclear disarmament, the US is once again trying to achieve military superiority.
Recent writings by senior leaders emphasize that this will not be tolerated. Writing in the latest issue of the theoretical journal Kommunist, Alexander Yakovlev, a member of the party Secretariat and one of Soviet leader Mikhail Gorbachev's closest advisers, said that parity would remain the cornerstone of Soviet foreign policy: a guarantee, he said, that ``the most warlike monopolistic circles of the US oligarchy'' will not be able to ``shape the world according to their interests.''
Washington's breaking of SALT II and its arms dealings with Iran are cited here as further proof of Washington's aggressive frame of mind. The Reagan administration violated SALT II on Saturday when it deployed a B-52 bomber modified to carry cruise missiles. By doing this, the US exceeded the overall limit on bombers carrying such missiles and ballistic missiles equipped with multiple warheads.
The Soviet leadership has yet to announce any specific retaliation for the US abandonment of the treaty. But Vorontsov told the press yesterday that Moscow had not yet received formal word on the White House move. Other officials have hinted recently that Moscow would retaliate.
On Iran, the Soviet and US governments have one point in common. Washington claims that hostages in Lebanon were not the main reason for arms sales to Tehran. The Soviets accept this. They feel that, from their point of view, US motivations were much more sinister.
The administration's main intent, Moscow feels, was once again to entice the Iranian government to join in the encirclement of the Soviet Union.
Washington was intending ``once again [to] turn Iran into an anti-Soviet bridgehead,'' an article in the latest edition of the weekly Literaturnaya Gazeta alleged. In the long run, the US was hoping to reopen the listening stations dotted along the Soviet-Iranian border in the time of the Shah, the article said.
The Soviet government newspaper Izvestia on Monday carried an unusually harsh attack on the Iranian government for its support of Afghan guerrillas. Until now, Moscow had tended to play down Iranian support for the guerrillas and instead had concentrated on improving relations with Tehran.
Some Soviet analysts, notably the newspaper commentator Alexander Bovin and specialists at the Institute of USA and Canada Studies, have long expressed pessimism about the possibility of reaching any arms control agreements with President Reagan. But a major unsigned attack by the party newspaper Pravda on West German Chancellor Helmut Kohl last week indicated that irritation with Western nations in general was growing. Unsigned or pseudonymous articles in Pravda are often expressions of official thinking.
The Pravda attack was only partly caused by Dr. Kohl's unflattering reference to Mr. Gorbachev in a recent Newsweek interview.
The article also devoted much space to attacks on positions that other West European nations share with Bonn: the nervous and negative reaction to Gorbachev's proposals at the Iceland summit in October and support for Mr. Reagan's Strategic Defense Initiative.
Moscow, it would appear, is becoming irritable and impatient with the lack of positive response to its foreign policy proposals.