Serb Softening Seen in Visit by Mediators : Bosnia: Russia’s special envoy is also received. He says rebels promised to end the siege of Gorazde.

In the first signs that Bosnian Serbs may relax their campaign of belligerence that followed NATO air strikes, two Western mediators were received by rebel leaders Wednesday, and Russia’s special envoy said he had won a Serbian promise to end the siege of Gorazde.

Russian Deputy Foreign Minister Vitaly S. Churkin clattered in a grimy armored personnel carrier between this government-held capital and the rebel stronghold in Pale, 10 miles to the east, in an effort to get Bosnian peace talks back on track.

“I think I’ve got a commitment from the Serbs that it’s not their intention to resume fighting, to attack, to take Gorazde or to shell the town,” Churkin said after briefing U.N. military and Western diplomatic officials on his talks with Serbian leaders in Pale.

Churkin was the only foreign mediator allowed across rebel siege lines a day earlier, when Serbs angered by the North Atlantic Treaty Organization bombings of their tank positions in Gorazde put up booby traps and barricades around U.N. encampments to make hostages of the peacekeepers.

After long talks with Serbian leaders in Pale, Churkin spoke optimistically about the prospects for a cease-fire in Gorazde and added that he could also foresee a truce covering all of Bosnia-Herzegovina to allow the Muslim-led government and Serbian nationalists to work out details of an ethnic division.

Despite describing the situation in Gorazde as tense, the Russian special envoy to the Balkans said there was understanding on both sides of the conflict “that in order to move onto other fronts, on other issues, we need to be sure about the situation in Gorazde.”

He declined to say whether Serbian rebel leader Radovan Karadzic or the hard-line military commander, Gen. Ratko Mladic, was willing to withdraw to the lines they held around Gorazde before this latest offensive, as ordered by U.N. Secretary General Boutros Boutros-Ghali.

Serbs have captured about 15% of the U.N. “safe haven” since March 30 in an offensive that torpedoed cease-fire talks and prompted the U.N. commander for Bosnia, British Lt. Gen. Michael Rose, to call for NATO air strikes on Sunday and Monday.

The Serbs have threatened to shoot down NATO warplanes and have condemned the U.N. mission as an enemy. A marked increase in sniping from Serbian positions was also noted Wednesday; at least four large-caliber shells detonated in Sarajevo, representing the worst cease-fire violations in nearly two months.

Senior U.N. officials and Charles Redman, the U.S. special envoy, had planned to visit Pale on Tuesday to discuss the standoff with the Serbian leaders but were informed by telephone that they would not be welcome.

But two diplomats who spent 16 months trying to broker a peace settlement in Geneva were allowed across the armed checkpoints that separate government and rebel territory.

“They know us. I think they want to keep peace negotiations going,” said Lord Owen, the European Union mediator for the mothballed Geneva talks. Owen and his U.N. partner in the peace talks, former Norwegian Foreign Minister Thorvald Stoltenberg, planned to return to Sarajevo today after overnighting in Pale.

More than 200,000 Bosnians, mostly Muslim civilians, are dead or missing due to fighting and “ethnic cleansing.”

In Gorazde, Fahrudin Bazic, a local official reached via ham radio from Zagreb, Croatia, said the situation remained desperate. But he said residents’ spirits were lifted after the NATO attacks.

“People are absolutely satisfied with air strikes and want more air strikes as long as tanks are on the outskirts of town,” he said, adding: “The mood among the people is that they are prepared to defend, to the last, what they’ve got. There had been some doubt before any sort of NATO intervention. But in the last two days, the two interventions improved the mood of the people in the city. Trust has returned (in) the world community and the world order, the U.S. and the rest.”

Times special correspondent Danica Kirka in Zagreb contributed to this report.