MOSCOW -- Russian leader Boris N. Yeltsin warned President Mikhail S. Gorbachev yesterday that pressuring Soviet republics to sign a new union treaty would backfire and said it might be wise to settle for a limited economic agreement as a first step toward preserving the Soviet Union.
Mr. Yeltsin stressed that the Russian Federation intended eventually to sign a union treaty, a position overwhelmingly endorsed yesterday in a vote of the Russian Congress of People's Deputies. But he said that rushing to conclude a treaty would only harden some republics' determination to quit the union.
Without mentioning Mr. Gorbachev by name but clearly having him in mind, Mr. Yeltsin denounced the "tone of ultimatum" in demands that the 15 republics sign the treaty.
"Instead of speeding up the process" of signing the treaty, he said, such a tone "could delay it or, in some cases, even block it."
"It would be an unforgivable mistake if haste in signing the treaty left outside the union republics that simply did not have time to make their choice or those whose justified demands were not taken into account and accepted," he said.
Instead, republics could be offered the chance to sign an initial economic treaty as the first stage in a full union treaty, Mr. Yeltsin said. Even the Baltic republics and Georgia, which have said they will not sign a union treaty, have expressed willingness to enter an economic pact.
But as if in answer to Mr. Yeltsin, KGB chief Vladimir A. Kryuchkov said in a televised statement made at Mr. Gorbachev's request last night that the security agency would use "all the means at its disposal" to prevent the collapse of the Soviet Union.
"A danger of the Soviet Union's disintegration has developed. Ethnic chauvinism is being fanned, and mass rioting and violence are being provoked," he said.
The KGB "has acted and will act as a barrier against the forces that seek to push the country into chaos," Mr. Kryuchkov said.
In stock phrases from the Cold War era, he charged that "extremist, radical groups" were receiving "moral and material support from abroad" and waging a "secret war" against the Soviet Union.
The KGB chief's words were remarkable for the absence of even a pro forma reference to the sovereign rights of the republics or the legalization of pluralistic, multiparty politics.
Mr. Kryuchkov's statement follows similar pronouncements by Defense Minister Dmitry T. Yazov and newly appointed Minister of Internal Affairs Boris K. Pugo, also made at Mr. Gorbachev's instructions.
The Soviet president's tactic seems to be to try to scare the rebellious republics into signing the union treaty voluntarily rather than risk the greater evil of an army or KGB takeover.
Mr. Gorbachev's haste in pushing for an early signing of a treaty to give new legitimacy to the union is dictated by evidence that the disintegration of the country is accelerating. He warned a Communist Party leadership meeting Monday that dissolution of the union would be a "cataclysm" with a huge cost in human lives.
From Georgia yesterday came the latest evidence to back up his fears. The republic's newly elected nationalist parliament voted to dissolve the 68-year-old autonomous status of the territory occupied by the Ossetian ethnic minority, a step likely to provoke a violent response and push the area toward civil war.
The Georgian parliament's move came a day after Southern Ossetia had declared that it was seceding from Georgia and would become a separate Soviet republic. The Ossetians' action, in turn, was prompted by what they saw as Georgian chauvinism, promoted in particular by the newly elected Georgian president, Zviad Gamsakhurdia.
Mr. Gamsakhurdia, in addition to vowing to lead Georgia to independence, regularly speaks of the need to "protect the rights of the Georgian people" against the alleged usurpations of pTC other ethnic groups. He opposes ethnically mixed marriages for Georgians.
Before the latest tension, there had been occasional violent clashes between Georgians and Ossetians in the mountainous territory on the Russian Federation's southern edge. Large-scale fighting occurred last year between Georgians and Abkhazians, members of another minority who live in an autonomous territory on the Black Sea coast.