Soviets Developing 4 New Nuclear Missiles, U.S. Believes : Superpowers: Cheney outlines concerns in meetings with Gorbachev, other Kremlin leaders.

Defense Secretary Dick Cheney, in a series of meetings Wednesday in the Kremlin, disclosed that the United States believes that the Soviet Union is developing four new long-range nuclear missiles.

Cheney expressed concern about the Soviet missile program in talks with President Mikhail S. Gorbachev and other senior leaders here and said that as long as the Soviet Union continues to modernize its nuclear forces, the United States will do likewise.

Speaking publicly of the new U.S. intelligence for the first time, Cheney told members of the defense committee of the Supreme Soviet that U.S. officials believe the Soviets are developing advanced versions of two land-based missiles and the nuclear missile launched by Typhoon-class submarines.

He said that while the United States welcomes cuts in Soviet conventional military strength, “with regard to strategic systems, we see a different picture.”

The committee, which in theory exercises oversight and budget authority over the Soviet military, appeared to be unaware of the missile modernization program before Cheney disclosed details of it.

Cheney’s disclosure came in the course of a visit aimed at lessening military tension between the two superpowers but which has instead served to highlight remaining large differences between the former Cold War antagonists.

In public and private meetings with the top Kremlin leadership, Cheney was challenged to seek peace, not war, in the Persian Gulf; to end U.S. support for the Afghan rebels; to withdraw U.S. forces from Korea; to end nuclear weapons tests, and to make deeper and faster cuts in the American military.

Cheney, in turn, admonished Moscow to reduce defense spending, radically revamp the economy and withdraw its military advisers from Iraq.

Despite numerous sharp exchanges, Cheney said the atmosphere was “entirely different” from what it was on previous visits in 1987 and 1983. Then, he came as a congressman; this visit is his first as secretary of defense.

“There is more dialogue and less posturing,” a senior official accompanying Cheney said. “They were much more forthcoming this time than last time.”

Responding to Cheney’s charge regarding the new Soviet missiles, Defense Minister Dmitri T. Yazov denied that the Soviets have begun a major new missile program.

“Why should we be developing new missiles when we are destroying several kinds of missiles and negotiating for a 50% reduction in strategic weapons?” Yazov said in a brief interview.

He was referring to the elimination of medium-range missiles under a treaty signed by Washington and Moscow in December, 1987, as well as the pending strategic treaty cutting long-range weapons.

The Soviet defense chief acknowledged that Moscow is preparing “modifications” for two classes of missiles, one land-based, the other carried on submarines. He would not elaborate.

“Since the creation of the ballistic missile, there have always been modifications,” he said. “But there are no totally new missiles.”

An aide to Cheney, who spoke on condition that he not be identified, said U.S. intelligence has determined that the Soviets are pursuing new versions of the SS-24 to be mounted on trucks and on rail cars, a new road-mobile version of the SS-25 and a new intercontinental missile for the Typhoon-class submarine.

Cheney raised the issue at a time when the United States is wrestling with the question of how and whether to modernize its land-based missile force.

Congress has been reluctant to fund either the MX missile or the smaller Midgetman weapon until Soviet trends are clear, the treaty on long-range missiles is completed and the Administration decides which missile option it wishes to pursue.

Cheney’s disclosure came in response to a question from Georgy A. Arbatov, one of the Soviet Union’s leading specialists on the United States and a member of the Supreme Soviet’s Committee on International Affairs.

Why, Arbatov wondered, was Cheney still so suspicious of the Soviet Union after the sweeping political and military changes that Gorbachev has instituted?

“We have been cautious in making changes in our fundamental military posture until we were certain that the changes in the Soviet Union were permanent,” Cheney replied.

He said he is still not satisfied that the Soviet Union does not represent a threat to the United States, because of its large and potent nuclear missile force, which continues to be modernized.

Cheney posed some challenging questions to his hosts, as well. Speaking before a joint session of the legislative committees on foreign affairs and defense, Cheney asked why Soviet military production remains so high.

He said that last year, the Soviets produced 140 ballistic missiles, two missile-carrying submarines and 1,800 tanks, while the United States built only 12 missiles, one ballistic missile submarine and 600 tanks.

Leonid V. Sharin, chairman of the Supreme Soviet’s Committee on Defense and State Security, replied that the Soviet Union is trying to convert its military-industrial complex to civilian production.

U.S. and Soviet leaders agreed to a new series of talks on how to reduce military forces, plan defense spending, close bases and redirect the economy from military to civilian production.

Today, Cheney will visit a Soviet airborne unit and an air defense command center. He will leave Friday for Paris, where he will consult with French leaders on the Middle East crisis and European security issues.