Vance Calls on Both Sides to Observe Truce in Bosnia : Yugoslavia: War ‘will be ruinous for all,’ the U.N.’s envoy warns. But he does not foresee deployment of peacekeeping troops.

U.N. envoy Cyrus R. Vance urged warring sides in Bosnia-Herzegovina on Wednesday to preserve a new truce but said the United Nations has no plans to send in peacekeeping troops.

“War is not the answer. It will be ruinous for all sides,” the former U.S. secretary of state said. “The situation in Bosnia is very, very serious and gives all of us great concern.”

In Washington, the United States accused the Serb-dominated federal government in Belgrade of fueling the bloodshed and threatened to turn Serbia into an “international pariah” unless it stops the war.

Fresh clashes erupted in Bosnia even as Vance arrived in Yugoslavia, dealing a further blow to a ragged cease-fire brokered Sunday by the European Community.

Vance, who acted as a mediator between warring Serbs and Croats in neighboring Croatia, said he believes the only solution is to try and keep the truce.

“I feel very, very strongly that everyone must get behind that,” Vance said. “I believe that those who think you can remove the problem by violence, by more killing, are dead wrong.”

Vance said the United Nations will send 100 military observers to Bosnia but that there are no plans to dispatch any of the blue-helmeted U.N. peacekeeping troops now deployed in Croatia.

“We are not going to put in any additional forces--blue helmets--in that we simply do not have any resources to do it,” he said.

Hundreds have reportedly died since Muslims and Croats voted for independence Feb. 29. Battles escalated after the United States and the EC recognized Bosnia as independent last week.

On Wednesday, the commander of the federal troops in Bosnia, Milutin Kukanjac, warned that the army will not tolerate “violent solutions” in Bosnia.

In Finland, the United States issued its own ultimatum, proposing that the Serb-dominated federal government be suspended from the Conference on Security and Cooperation in Europe if it doesn’t stop fomenting violence in Bosnia-Herzegovina.

Such a move to isolate a member of the group would be unprecedented. The conference promotes human rights.