President Mikhail Gorbachev says he fears bloody social upheaval if he fails in his efforts to reach a power-sharing agreement with Russian republic President Boris Yeltsin.

Gorbachev met Sunday with Yeltsin and pressed him to sign a new union treaty as a means of preserving the federation of 15 republics, to be renamed "The Union of Sovereign Republics.""The Union of Sovereign Republics, to use the military idiom, is the last trench line," Gorbachev told senior military officers at a Kremlin meeting on Tuesday.

"The disintegration of the state begins beyond," he said in remarks quoted by the official news agency Tass. Dissolution of the Soviet Union "could turn into a bloodbath," Tass paraphrased him as saying.

"A situation may arise that will be worse than during the Cultural Revolution in China," Gorbachev said, referring to the tumultuous final decade of Mao Tse-tung in China from 1966-76, according to Tass.

Mao's attempt to revive revolutionary fervor in China sparked a violent struggle for power. An estimated 1 million people died.

Gorbachev made a similar comment in March, grappling with a crisis over Baltic separatism and facing a Russian parliamentary election that eventually put Yeltsin in power of the country's largest and most populous republic.

Gorbachev and Yeltsin met for five hours on Sunday in a major initiative to end the paralysis of power in the Soviet Union.

Gorbachev confirmed Yeltsin's statement that the two had set up commissions to decide how to divide authority between the central Soviet government and the Russian government, which has emerged as an independent force since Yeltsin was elected its president in June.

The Soviet and Russian commissions will work while representatives of the 15 republics try to negotiate a new union treaty to replace the 1924 charter that forms the basis of the Union of Soviet Socialist Republics.