Russia May Back Stronger Sanctions Against Serbs : Europe: Moscow won’t rule out military action, envoy says. Foreign minister leaves for peace talks.

MOSCOW —  Russia’s special envoy to Belgrade said Monday that Moscow might back stronger sanctions against Bosnian Serbs, perhaps even military intervention, if they keep defying a U.N.-sponsored peace plan.

The envoy, Vitaly Churkin, issued the warning as Russian Foreign Minister Andrei V. Kozyrev left for talks in Europe and the United States to promote the peace proposal by U.N. envoy Cyrus R. Vance and European Community negotiator Lord Owen.

Because of their common Slavic heritage, Russia wields considerable influence over the Serbs, and Churkin’s remarks indicated a toughening stance against their refusal to accept the peace plan.

“The position of the world community in the application of the Vance-Owen plan should be delicate but firm--particularly toward violators,” Churkin told reporters.

Asked about military intervention, he repeated several times that he “could not exclude” Russian support in the U.N. Security Council for any measure, even military action.

While backing nearly every joint diplomatic action in Bosnia-Herzegovina, President Boris N. Yeltsin’s government has refused to commit Russian troops to an intervention force. Moscow appears to be leaning toward a policy like the one it adopted during the Persian Gulf War: endorsing international military action but not taking part.

Defense Minister Pavel S. Grachev reiterated that stance Monday, saying it is his “firm decision” to keep Russian soldiers out of combat in the Balkans. But he said he is not opposed to sending monitors to Bosnia “for enforcing a peaceful resolution.”

Kozyrev left Monday for a week of talks aimed at trying to save the Vance-Owen peace plan, which would divide Bosnia into 10 ethnic provinces among the three warring factions--Muslims, Serbs and Croats. By all accounts, Bosnian Serbs rejected the plan in a weekend referendum.

“We don’t have to wait until the last Bosnian fighter endorses the plan,” Kozyrev said before leaving for talks in Berlin, the Croatian city of Split, Belgrade, Rome, Washington and New York. “We can put out the fire . . . step by step.”

Churkin, a deputy foreign minister, said Kozyrev will ask the Security Council at a meeting late this week to endorse such a step-by-step approach, setting up autonomous provinces in areas where there is no fighting. He criticized Bosnian Serb leader Radovan Karadzic for claiming that the referendum has killed the peace plan.

“It is our view that there are not so many hard-liners among the Bosnian Serbs and they will be further isolated,” Churkin said. He predicted that support for the peace plan by Serbian leaders in Belgrade and dwindling supplies of food in Bosnia would force them to accept the plan.