MOSCOW -- President Mikhail S. Gorbachev blasted "nationalists and extremists" and said their activities threaten to turn the Soviet Union into another Lebanon.
Addressing the first gathering of top Communists since a major congress reorganized the troubled ruling party in July, Mr. Gorbachev said the most important task for the party is to "resist pressure from separatist forces."
"Here lie the roots of violations of law and order and our economic difficulties, which are having a serious effect on people's lives," he told Central Committee members gathered in the Kremlin, the Tass news agency reported.
"Let's be frank. If these tendencies are not overcome and are allowed to develop further, the country could really be threatened by Lebanonization with all its well-known consequences," he said.
Mr. Gorbachev, who is also the party's general secretary, said separatists are duping people and "creating an atmosphere of hatred and terror."
He said Communists should "expose the insidious tactics of the nationalists and extremists. We need both for the bold truth to be spoken and for the force of the law."
The Tass report indicated that he did not refer to specific cases. Mr. Gorbachev has accepted that the rights of the 15 Soviet republics must be greatly enlarged in a proposed "Union of Sovereign States" but balks at outright independence.
In his speech, Mr. Gorbachev may also have had in mind the "second generation" of sovereignty and independence demands from many smaller jurisdictions within republics. In Moldova, formerly Moldavia, for instance, an ethnically Russian region has declared its autonomy, as has another region inhabited by the Gagauz nationality. Moldovan officials have declared the breakaway attempts illegal and have arrested at least one leader of the Gagauz movement, Leonid Dobrov. Moldovan nationalists have declared the separatist leaders "enemies of the Moldovan people" and suggested that they may face vigilante violence.
Meanwhile, some Moldovan activists even propose seeking union with bordering Romania, whose language and culture the Moldovans share.
In a recent meeting with the Moldovan leaders, Mr. Gorbachev told them he thought their own intemperate demands for independence from the Soviet Union had led naturally to the separatist movements within Moldova.
Yesterday, Mr. Gorbachev warned his colleagues against "the inertia of old thinking," saying the party's survival will depend on its adjustment to the coming market economy.
Officials revealed yesterday that hundreds of thousands of members have left the Communist Party this year -- 371,000 in the first six months and 311,000 in July and August. Mr. Gorbachev suggested that part of the problem is party officials' clinging to old dogma.
"Yes, we are encroaching upon socialism, but only the socialism that was built bureaucratically, under which the country veered off the path it embarked upon in 1917," he said.
Mr. Gorbachev's familiar assertion that the country is merely returning to pure Leninist socialism after the distortions of Josef V. Stalin and Leonid I. Brezhnev finds fewer and fewer believers these days among Soviet citizens. But as party leader, Mr. Gorbachev is obligated to explain whatever he does as somehow inspired by socialist ideals. His rival, Russian Federation leader Boris N. Yeltsin, who left the party in July, has been able to embrace the idea of a Western-style free-enterprise system with fewer reservations.
The deputy party leader, Vladimir A. Ivashko, announced the new statistics on party membership yesterday. Although the numbers of those who have formally quit amount to only a small fraction of the party's estimated 18 million members, many more are said to have stopped paying dues and to have left the party in all but name.
Mr. Ivashko characterized the country's economic situation as grave, with industrial output declining 0.9 percent in the first nine months of the year: "Shortages are all-pervasive, the speculation and price rises that have hit the consumer market poison the lives of millions of Soviet people every day."
But he said rumors of impending famine are unfounded.
He said the party backs the transition to a market economy but will insist on strong protection for people during the changeover. He repeated a call by Mr. Gorbachev for a referendum to decide whether land will be sold into private ownership.
Mr. Ivashko told the 412 Central Committee members, plus dozens of other party officials invited to the plenum, that "the union no longer exists -- not in its old form nor in a new one."
But he said it was no use lamenting the end of the "unitary" Soviet state, which had outlived itself.