President Mikhail S. Gorbachev urged the Soviet people Friday to vote "yes" on a referendum to preserve the union, promising that a favorable vote would bring renewal, not a return to the "old order."

Gorbachev's speech came on the heels of a visit by U.S. Secretary of State James A. Baker III, during which Baker said the United States supports Gorbachev's efforts to continue reform, both toward "political pluralism and economic reform toward a free market goal at some point."However, after his visit with Gorbachev, Baker - who failed to break a stalemate on arms-control treaties with the Soviet Union - dined with the reformist mayors of Moscow and Leningrad, the president of the republic of Georgia and the prime ministers of the republics of Armenia, Georgia and Kirizia.

Without explanation, Gorbachev's most prominent critic, Boris Yeltsin, president of the Russian Federation, did not attend.

In his final plea before Sunday's balloting, Gorbachev said a successful referendum would mean continuing reforms, while defeat would bring "misfortunes and disasters . . . a shock of unheard-of proportions."

"My firm conviction is that if there happens to be a major split in society, there will be no winners, only losers. We all will lose," he said on national television.

A "yes" vote "is a guarantee that never again will the flames of war scorch our country, which already has survived many trials," he said. Public opinion polls predict a victory for Gorbachev.

Yeltsin, Gorbachev's chief political rival, accused the Kremlin of a "propaganda campaign" to scare people into voting for preserving the union."However the referendum ends, the union will not fall apart. Don't frighten the people! Don't sow panic!" Yeltsin said earlier Friday in a speech broadcast on Radio Russia and on a freewheeling TV station in Leningrad.

Gorbachev did not mention Yeltson in his speech, which preceded the nightly TV news, but appealed to the people to put aside factional interests for the vote.

"This is a question of such scale and of such importance that stands beyond the interests of separate parties, social groups, political and public movements," Gorbachev said, seated in front of a red curtain.

Approval of the question and conclusion of the Union Treaty - the document that will redefine the relationship between the republics and the central government - "will make it possible to put an end to the destructive processes that are under way in our society, to turn decisively to the restoration of normal work and life conditions," Gorbachev said.

Yeltsin said he was denied time on national TV, although the official Tass news agency said a spokesman for the state-run TV monopoly invited the Russian leader to make an address hours before Gorbachev.

Instead, Yeltsin turned to Radio Russia, which reaches about 60 percent of the Soviet population.

Yeltsin did not say how he would vote. But he repeated a theme sounded by many Soviet and Western analysts that the referendum question was so murky that the results would not give Gorbachev a clear answer to any of the momentous decisions he faces.

"Many (voters) are confused. Above all, the question is not clear and ambiguously phrased," said Yeltsin.

Yeltsin said in his speech that "most of the citizens of our republic are for the union. This was clear even without a referendum." But Gorbachev should give more power to the republics, no matter how the vote goes, he said.

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Soviet referendum

Background: Gorbachev ordered the referendum to show there is popular support for holding the 15 Soviet republics together. Reformers want to turn it into a referendum on Gorbachev's six years in power.

- The question: "Do you consider it necessary to preserve the Union of Soviet Socialist Republics as a renewed federation of equal, sovereign republics in which human rights and freedoms of any nationality (people of all ethnic groups) will be fully guaranteed?"

- Eligible voters: About 200 million.

- Not participating: Lithuania, Latvia, Estonia, Georgia, Armenia and Moldavia. However, voting on the question will be held in some isolated, heavily Russian, areas of Latvia, Lithuania, Estonia and Moldavia.

- Penalty: Anyone interfering with the referendum faces up to five years in prison, two years in labor camp or a fine of 5,000 rubles.

- Results: Preliminary results won't be available before Monday. Final results won't be available for a week.