Soviets Act to Tighten Arms Grip : Security: Moving to allay Western jitters, the defense minister says all strategic weapons will stay under Kremlin control. The Ukraine’s military plans have worried U.S.

Soviet Defense Minister Yevgeny I. Shaposhnikov, moving to allay Western jitters triggered by the Ukraine’s claims to the nuclear weapons based on its territory, declared Saturday that all strategic arms will remain tightly under the Kremlin’s control.

To avoid further political wrangling over the armed forces, Shaposhnikov called on the republics of the collapsing Soviet Union to sign a treaty creating a “defense union of sovereign states.”

He told the Tass news agency that the Defense Ministry is working out guidelines on the status of the armed forces in the republics but that the central government will continue to control the Soviet Union’s massive nuclear arsenal.

“There is every basis to consider that nuclear weaponry will not slip away to separate republics,” Shaposhnikov said. “It will remain in the hands of the center.”

The Ukrainian Parliament raised Western worries about the possible birth of a new nuclear state by adopting a declaration last week effectively barring the transfer of Soviet nuclear weapons beyond its borders and giving preliminary approval to the creation of a national army planned to total more than 400,000 troops by 1995.

And on Saturday, the Central Asian republic of Kazakhstan, which also provides bases for Soviet strategic weapons, reiterated that it wants joint control with the Kremlin over the nuclear arms on its territory.

The Ukrainian moves prompted Bush Administration officials to declare that the United States would not recognize the Ukraine’s independence if it seeks to become a major military power.

German Foreign Minister Hans-Dietrich Genscher pointedly told Soviet President Mikhail S. Gorbachev on Saturday that Germany, while expanding its ties with the republics, wants to deal with only one nuclear superpower to its east.

“The process of the disintegration of the Soviet Union should not lead to the appearance of new nuclear states on its territory,” Genscher told reporters after meeting Gorbachev.

Ukrainian politicians, however, complained that the Western reaction to the republic’s plans was alarmist.

Les Taniuk, a member of the Ukrainian Parliament’s leadership, said that the West was overreacting because Moscow, intent on preserving a Russian military monopoly in the region, resorted to “pure disinformation” about Ukrainian nuclear intentions.

“The Ukraine is not taking jurisdiction over the weapons,” Taniuk said. “But they’re located here, and we just don’t want anyone to be able to launch them.”

Dismissing American fears of Ukrainian military ambitions, Taniuk said, “It’s strange that they’re afraid of increasing military forces. There are now 1.5 million (Soviet) troops on Ukrainian territory. We’re proposing a smaller force of about 400,000 for now, and even that will be reduced to about 150,000 to 200,000 eventually.”

A Western official in Kiev who asked to remain anonymous said that the Ukrainian declaration did not appear to contradict the republic’s earlier proclamation that it wants to become a nuclear-free zone.

“It acknowledges joint control over nuclear weapons during a transition period,” he said. “There are various kinds of joint control, including a ‘double key,’ ” a system allowing the missiles with nuclear warheads to be launched only if the Ukraine agrees.

Lawmakers said the Ukrainian claim to some control over nuclear arms in the Ukraine came in part as a response to proposals in Moscow that Russia, as the heir apparent to the Soviet Union, should take all nuclear weapons onto its own territory.

“If Russia has a monopoly on nuclear weapons, it will be very destabilizing,” Taniuk said.

In its fight for nuclear control, the Ukraine is challenging the Soviet military establishment, the vast republic of Russia and much of world opinion and its concerns about nuclear proliferation.

The Ukraine’s position has a certain strength. As the second richest of the remaining 12 republics, with a population of 52 million in a territory larger than France, it is the linchpin in Gorbachev’s attempts to refashion the Soviet Union into a workable new country. Ukrainian presidential elections and a referendum on independence on Dec. 1 may determine the union’s fate.

The Soviet Defense Ministry acknowledged last week that the Ukraine, as a sovereign republic, has the right to its own army.

But Gorbachev has denounced the attempts by republics to “nationalize” military property, and Shaposhnikov told Tass that in terms of nuclear weapons, “all the republics are agreed that they must fulfill their obligations to the West and other partners.”

This means strategic as well as tactical weapons, he said.

At this point, Shaposhnikov stressed, all Soviet military units in the country’s 12 remaining republics and in the three newly independent Baltic states should obey the Defense Ministry, as agreed upon by the national Parliament in early September, and all defense decisions should be coordinated with the country’s ruling State Council.

With the country collapsing, Shaposhnikov said, a transitional period should be announced and a treaty preserving the country’s “military-strategic space” concluded.

The Defense Ministry is meanwhile working on a document to define the role of Soviet troops in the republics, he said. Their duties, he said, should be defined as defending the borders of the republic and the country, staying out of the republic’s internal affairs, carrying out maneuvers with the permission of the republic and abiding by the area’s ecological rules.

Because so many republics have decreed that their youths can serve only on their home territory, he added, only recruiting soldiers on a volunteer basis with higher pay and agreed contracts will save the army from “total collapse.”

A detailed program for making up a new army, moving away from the massive conscription of old and toward a volunteer army, will be ready soon to be presented to the State Council, he said.

Special correspondent Mary Mycio in Kiev contributed to this report.