Yugoslav Chief Denies Serbs Are at Fault : Bosnia: President Cosic denounces Western nations over sanctions. His stance indicates intent to tough it out.

BELGRADE, Yugoslavia —  As fighting flared across Bosnia-Herzegovina on Wednesday, Yugoslav President Dobrica Cosic insisted that Serbs are in no way responsible for the Balkan crisis and accused Western countries of condemning his compatriots to a “concentration camp” by imposing sanctions.

Cosic’s injured pose and his insistence that no change of policy is called for on Belgrade’s part indicated that the Serbian and federal leaderships plan to tough out the latest U.N. punishment rather than succumb to its aim of breaking the Serbs’ will for war in the region.

“War and peace are not in Serb hands,” insisted Cosic, a revered nationalist writer and the ideological godfather of the drive for a Greater Serbia. “The key to peace lies in Washington, Bonn, London and Paris. We are just a modest and sincere partner in the quest for peace.”

Evoking the Serbian self-image of martyrdom for which his works are renowned, Cosic described the tightening of U.N. sanctions against his country as wholly unjustified and the result of an ignorant international community that has long failed to understand Serbs.

“Yugoslavia finds itself in virtually total isolation, in a kind of concentration camp on whose borders NATO planes patrol and the global police force watches us,” the president said. “The question is whether they are going to be able to liquidate us by famine, or will they find it more efficient to destroy us by showering us with missiles?”

The bespectacled, 71-year-old president said Belgrade had no inkling that Serbian allies in Bosnia would reject a Western-mediated peace plan for the republic--the action that triggered imposition of harsher sanctions on Serbia and Montenegro, the last two republics left in Yugoslavia.

But Cosic also defended the Bosnian Serbs, claiming that the settlement proposed by mediators Cyrus R. Vance of the United Nations and Lord Owen of the European Community failed to provide sufficient guarantees for “the survival of the Serbs” among their Bosnian Muslim and Croatian enemies.

Nationalist politicians like Cosic and Serbian President Slobodan Milosevic have portrayed the Bosnian war as an inevitable explosion of inter-communal hatreds instigated by Western governments that are bent on destroying federal Yugoslavia by granting diplomatic recognition to the republics that seceded from it.

Most Western observers see the Bosnian strife as part of the Serbs’ campaign for an expanded nation uniting the republics of Serbia and Montenegro with Serbian minorities in other Balkan regions.

More than a year after the Serbian revolt against Bosnian independence began, fighting has spread across most of the republic and triggered bitter reprisals. Some of the most savage battles in recent weeks have been between supposedly allied Muslims and Croats, as Croatian nationalists, encouraged by the West’s failure to stop Serbian aggression, have acted in kind to seize territory for a Greater Croatia.

New clashes between Croats and Muslims were reported Wednesday between the towns of Busovaca and Kiseljak, just west of Sarajevo, despite a cease-fire ordered last week by the Bosnian Muslim and Croatian leaders.

The Office of the U.N. High Commissioner for Refugees said that sporadic fighting also had broken out between Serbian and Muslim forces outside the U.N.-protected town of Srebrenica.

A Serbian offensive continued against a Muslim stronghold in the republic’s northwest, with rebels raining artillery shells on the town of Velika Kladusa in a region known as the “Bihac pocket.”

The gunmen, from Serb-occupied areas of Croatia, had invaded a day earlier in an offensive that seemed to raise the likelihood of Western intervention.