MOSCOW, DEC. 10 -- As his personal emissary picked up his Nobel Peace Prize in Oslo, Soviet President Mikhail Gorbachev made an emotional appeal today to the Communist Party leadership here to wage a political battle against nationalist leaders in the nation's republics.

Denying charges that Moscow was trying desperately to hold onto an empire, Gorbachev told a plenary session of the party Central Committee that the Soviet Union faced "no greater danger" than "dyed-in-the-wool extreme nationalists." He said that in some republics, the Communist Party had "lost its bearings" and failed to hold power.

In Georgia, Armenia, Moldavia and the three Baltic republics, the Communist Party has become a minority opposition force in legislatures dominated by parties supporting either outright independence or at least a far greater degree of sovereignty than Gorbachev is willing to permit.

Gorbachev's angry attack on nationalist leaders was a further indication of his increasingly hard line on the national question and underscores his apparent sense of urgency about getting the republics to endorse his plan for revision of the treaty that binds them to the central government in Moscow. The Balts and the Georgians, however, already have declared their refusal to sign, saying that Moscow merely wants to maintain centralized power over its "internal empire."

"We can answer these slanderers in this way: 'Esteemed gentlemen, you are mistaken by more than 70 years,' " Gorbachev said. "The Russian empire ceased to exist in 1917. In the ensuing years there was much to be condemned -- injustice and crimes against many nations. But let no one cast doubt on the gains achieved by the nations united within the U.S.S.R."

Since the Communist Party reluctantly gave up its monopoly on power in March, dozens of parties have formed and some have won significant electoral victories around the country. Meanwhile, hundreds of thousands of party members have abandoned the ranks. Boris Yeltsin, president of the Russian republic, quit the Communist Party last July, as did the mayors of Moscow and Leningrad, the country's two biggest cities.

In an attempt to retain at least some popularity, some Communist organizations in the republics have dissociated themselves from Moscow. Last weekend, the Lithuanian party organization changed its name to the Democratic Labor Party.

"It is up to party committees and organizations to work with all factions and groups within elected bodies," Gorbachev told the Central Committee. "They should exchange ideas, work out a general line up to creating a broad democratic movement in favor of maintaining and renewing the union."

Gorbachev himself has a complicated relationship with his own party. Although he has called himself a "convinced Communist," his definition of the term and his vision of the future of the economic and political system are far less traditional than those of the vast majority of the apparatchiks who form the party's senior leadership. Gorbachev has made his suspicion of the party apparatus apparent, and many of the party's old guard see him as a radical who "lost" Eastern Europe and has made too many concessions to the younger generation of non-Communist politicians.

Gorbachev has been able to outmaneuver many of his more conservative rivals, but many of his non-Communist critics have said he must abandon the party if he is ever to carry out full-scale economic reform. The official news agency Tass, however, denied that Gorbachev was planning to give up his role as party general secretary.

The editor of the Communist Party daily, Pravda, Ivan Frolov, told the Reuter news agency that the party could hold an special congress in late 1991 to map out its ideological program and to try to solve its membership crisis. He said that as many as half the party's 18 million members may quit.

At the plenum, which continues Tuesday, Gorbachev is expected to discuss details of the Treaty of the Union as well as his plans to widen his presidential powers at a session of the Congress of People's Deputies, the nation's highest legislative body, which opens Dec. 17.

Giorgi Shakhnazarov, one of Gorbachev's closest aides and one of the authors of the new draft treaty, said the republic's legislatures could either decide to join the new union, which would retain a great measure of power for Moscow, or can go through a secession process that would involve a popular referendum and a waiting, or negotiation, period of at least five years.

Gorbachev's decision to attend the closed Central Committee meeting rather than pick up his Nobel Peace Prize in Norway was seen as a concession to the realities of his imperiled domestic political standing. There was a small anti-Gorbachev demonstration outside the Norwegian Embassy in Moscow today, but if the Soviet leader had gone to Oslo, with the economy failing so miserably, he likely would have sparked a measure of public displeasure.

Instead, Soviet Deputy Foreign Minister Anatoly Kovalyov accepted the award, as well as a check for $715,000. Reading a message from Gorbachev, he said that while the year provided a "unique opportunity for reason and the logic of peace to prevail over that of war and annihilation, there are some very grave threats that have not been eliminated: the potential for conflict . . . aggressive intentions and totalitarian traditions."

Gidske Anderson, the chairman of the Nobel prize panel, said the ceremony was not the place to discuss the Soviet Union's domestic difficulties and expressed hope that the award will "be recognized as a helping hand in an hour of need."