Gorbachev Pleads for Unity : Vows to Quit if Disintegration Can’t Be Halted : Soviet crisis: A coalition of ‘centralizers’ joins in effort to preserve nation. Yeltsin warns the republics of possible border revisions.

His country crumbling even as he sat in the Kremlin, Soviet President Mikhail S. Gorbachev made a desperate plea Tuesday for preserving the Soviet Union and said he will resign if its disintegration becomes irreversible.

Speaking in emotion-laden tones to the Supreme Soviet, Gorbachev said the most “tragic result” of last week’s failed right-wing coup--mounted by reactionaries who oppose Gorbachev and any devolution of Moscow’s powers--was that it spurred the very “centrifugal tendencies” it was meant to halt.

“A real threat of the collapse of the union state has arisen,” Gorbachev warned, even as Moldova became the seventh of the 15 republics to declare independence.

Although a day earlier he had dramatically given the green light to Soviet republics that want to secede, citing their “right of independent choice,” he again called for a Union Treaty between the republics and the national government, a power-sharing plan that leaders of some republics say now belongs to history.

Gorbachev, who thumped the lectern with his hand for emphasis, vowed to do everything in his power “not to let things cross the line beyond which the disintegration of our union becomes imminent.”

“Otherwise, I will resign,” said Gorbachev, who has led the Soviet Union for 6 1/2 years, unleashing a torrent of social, political and economic forces that now threatens to sweep him from the scene. If the union is destroyed, he said, “We will have nothing.”

Gorbachev may have been emboldened by a new force rapidly forming in the legislature--an unlikely coalition of “centralizers,” mostly Russians, alarmed by what they see as the squandering of what was bequeathed them by the czars and commissars. They are opposing leaders of the outlying republics, now more eager than ever to break decades, sometimes centuries, of rule from Moscow.

Russian Federation President Boris N. Yeltsin, now the No. 1 decision-maker in domestic politics, arrayed himself with the centralizers by endorsing the signing of a new agreement between the republics. But it was unclear what sort of links he wants, and he ominously noted that Russia “reserves the right” to revise its borders with republics that choose to leave the Soviet Union.

In other developments:

* As British Prime Minister John Major announced that he would be the first Western leader to visit Moscow to discuss the Soviet situation with Gorbachev and Yeltsin this weekend, the European Community agreed to recognize the independence of Latvia, Lithuania and Estonia, the three states on the Baltic coast that were occupied in 1940 by Soviet dictator Josef Stalin.

* Criminal proceedings for “high treason” were started against the eight members of the State Emergency Committee that briefly usurped Gorbachev’s powers, Tass reported. If convicted, they could be imprisoned from 10 to 15 years or shot.

A criminal investigation also was launched of the Leningrad Communist Party organization, one of the most anti-reformist in the country, for possible complicity in the coup. And the U.S.S.R. State Bank, saying Communist apparatchiks are trying to launder huge sums, mostly dues from the rank-and-file or income from government property, by buying into profit-making businesses, recommended that local government bodies impound party assets.

* The Democratic Union, the first rival party formed to challenge the Communist grip on power, denounced the ban on Communist Party activities and the shutting of newspapers, including Pravda--steps taken in tandem by Yeltsin and Gorbachev--as the “beginning of a dictatorship.”

* Yegor Yakovlev, the crusading editor in chief of the weekly Moscow News, one of the most daring voices of glasnost, was named by Gorbachev to head the Gostelradio State Broadcasting Co., replacing Leonid P. Kravchenko, who was fired for serving the putschists. And the Moscow International Book Fair, a premiere cultural event in the Soviet capital that had been scheduled for Sept. 3-9, was canceled, Tass said.

Russian Fears

In the wake of the failed coup and the collapse of Gorbachev’s power and prestige, the new role of Yeltsin’s Russian Federation as a substitute and successor for the Soviet government is now very much on the minds of Supreme Soviet members.

“We, Russian leaders, are not acting as Big Brother toward the other republics--we are acting as responsible leaders who cannot permit total disintegration,” contended Oleg Rumyantsev, secretary of a commission drafting a new Russian constitution.

But reacting to the greatly inflated demands of republic leaders, the centralizers--who include both radicals and archconservatives--said some functions in a superpower must be exercised by a central government alone, for example, the control of nuclear arms.

“Today we have the national constitution, the national power bodies and, while we recognize declarations by the republics of their statehood and independence, we must say firmly: There are issues and matters that are exclusively of union competence and which no republic can resolve independently,” said Leningrad Mayor Anatoly A. Sobchak, a progressive.

Some deputies warned that the world is now witnessing the rebirth of the Russian Empire--with Yeltsin in the guise of the czar--on the ruins of Soviet and Communist Party rule.

But Gorbachev, now politically wedded to Yeltsin, who saved him from last week’s right-wing plot, called that notion ridiculous.

“Don’t be afraid if somebody says that the concept of a Russian Empire is being realized today,” said Gorbachev, himself an ethnic Russian. “Don’t believe that the Russian president has ousted the president of the country and ignores the republics. Neither Russians, nor Yeltsin and the Russian leadership, have such ideas.”

Gorbachev’s assurances notwithstanding, Russian hegemony is precisely what some of the lawmakers said they feared. “I must raise my voice against the impermissible threats to make territorial claims, the impermissible threats to re-create the imperial structures under different names,” one radical member of the legislature said.

An emergency session of the Congress of People’s Deputies, to convene next Monday, will be faced with the question of Gorbachev’s political fate, since it can strip him of the post of president that he has held since 1988.

Just as important, the Congress must determine whether sentiment in the country favors something like Gorbachev’s federal Union Treaty, or whether the 15 Soviet republics are fated to go their own ways and become independent countries.

By the end of his speech--in which he called upon his countrymen to refrain from “anti-Communist hysteria” that would hurt the millions of rank-and-file members of the party, Gorbachev sounded desperate.

“You understand, I need your help,” he said at one point.

A New Union?

Both Yeltsin and the president of Kazakhstan, Nursultan Nazarbayev, called for the signing of a new “union agreement” that would take into account the changes the country has gone through since the coup and allowing the republics to form some sort of central government in Moscow.

However, that government would surely have a greatly weakened role, based on Nazarbayev’s quest for the transformation of the once-monolithic Soviet Union into a loose “confederation” of independent countries that would leave Moscow with little more than chores like coordinating air and rail service.

According to Tass, Yeltsin also said that the Russian Federation is now asserting the right to revise its borders with republics leaving the Soviet Union--a statement that threw a chill into many representatives from the outlying republics, some of whom judged it as virtual blackmail to bar them from seceding.

“Territorial claims are very dangerous and in any case can end with great complications for people,” Ukrainian leader Leonid Kravchuk told a news conference in Kiev. He said he is seeking clarification from Yeltsin of what the Russian leader meant.

The Ukraine declared its independence last Saturday, subject to a Dec. 1 referendum, in what has been the heaviest blow to date to Gorbachev’s campaign to preserve the Soviet Union, founded in 1922 as something resembling a single nation-state.

At the Supreme Soviet, Gorbachev said that he, Yeltsin, Nazarbayev and Askar Akayev, the president of a third Soviet republic, Kirghizia, agreed at a meeting earlier in the day “that the U.S.S.R. should be preserved as a union of sovereign states.”

But the import of that was uncertain, since the only practical measure they agreed on, by Gorbachev’s account, was the start of work on an economic cooperation agreement for the 15 republics--something that would not blunt the republics’ independence drives.

The presidents agreed to try to complete negotiations on the economic agreement within 10 days and to hold separate, parallel negotiations on political unity, the Associated Press reported Akayev as saying. All the republics have said they want to continue economic ties, since their industries are tightly linked and would suffer from a break in trade.

Kazakhstan’s Nazarbayev was reported by the Interfax news agency as having “no particular optimism” about Gorbachev’s latest attempt to keep the union whole. Nazarbayev on Monday reversed his previous support for the preservation of the union.

In any event, the dispute made strange bedfellows out of onetime adversaries.

Col. Viktor I. Alksnis of Latvia, a member of the archconservative Soyuz group and no political ally of Sobchak’s, admitted he felt amusement at hearing progressives like the Leningrad mayor speaking in favor of a “strong center.”

“Life itself will make us create a center,” Alksnis said. “The republics will start conflicts between themselves--Yeltsin vs. Nazarbayev, Yeltsin vs. Kravchuk--and simple people will fall victims to such conflicts.

“The people,” he added, “will finally demand a man who will be able to say, ‘Break!’ and take the leaders to different corners of the ring. Kravchuk will never agree to have Yeltsin over him; Yeltsin will not agree to be a subordinate to Kravchuk. Finally, everybody will have to agree to let somebody be above everybody. . . .”

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