US Offer of Military Support Seen to Boost Pressure on Serbs

SIX warships of the US 6th Fleet carrying 2,200 marines Wednesday cruised the Adriatic Sea following Washington's offer to use military muscle to protect the United Nations humanitarian operation in Sarajevo, the war-torn capital of Bosnia-Herzegovina.

The United States military presence was also intended to boost the already intense international pressure on the Yugoslav Army-armed Serbian Democratic Party (SDS) to lift its siege on Sarajevo and allow a resumption of negotiations on ending the bitter conflict in the newly independent former Yugoslav republic, Western diplomats say.

"Things are now on the peace track and moving forward," one Western diplomat said. "This can be interpreted not as a threatening move but as a strong show of support for the peace process."

"I think it reflects the fact that to get the attention of the people with the guns, you need to use this kind of language," the diplomat said. Significant progress

A major step toward ending the bloodshed in Sarajevo came Monday when SDS forces withdrew their heavy weaponry from the city's airport and turned the facility over to the UN Protection Force (UNPROFOR) for humanitarian aid flights.

Western diplomats said SDS fighters also continued running convoys across the airport runway through holes cut in its perimeter fence from their base in a former Yugoslav Army barracks in suburban Lukavica.

The UN resolution authorizing the operation also calls for the creation of a "security zone" around Sarajevo that would ensure the safe distribution of food and medicine to the estimated 300,000 people trapped by an almost three-month Serbian siege.

Cedric Thornberry, the chief of UNPROFOR civil affairs, conceded that negotiating that part of the plan will be more difficult than the long-delayed airport hand-over because it would require a disengagement of the warring factions, effectively forcing the SDS to halt its drive to partition the predominantly Muslim Slav city into ethnic districts.

"In order to do this, we are going to have to have continuing political support from the leading powers," the diplomat said.

The Bush administration was apparently aware of that in making military forces available to the UN, a step that the 12-nation European Community took over the weekend. Western diplomats said they believe President Bush was also forced to act in line with his often-stated determination to maintain America's leading role in the international arena.

He had been strenuously resisting such a commitment since Bosnia-Herzegovina's embattled government of Muslim Slavs, Croats, and moderate Serbs began pleading for international intervention weeks ago.

But US diplomacy had been increasingly eclipsed in the crisis by assertive French involvement, highlighted Sunday by French President Francois Mitterrand's courageous visit to Sarajevo.

Serious questions remain as to whether the SDS and its chief military and political patron, communist-ruled Serbia, will respond to the US move and rein in its military offensive to carve a self-declared Serbian state out of multi-ethnic Bosnia-Herzegovina.

Such a development, Western diplomats said, would be tantamount to yet another in a recent string of Serbian military setbacks, including the loss of Sarajevo airport.

These setbacks could threaten the credibility of the SDS hierarchy and President Slobodan Milosevic of Serbia by forcing them to compromise on a political settlement that could give rise to violent objections from radical Serbian field commanders.

The initial Serbian reaction to the US move was not encouraging. SDS gunmen showed no sign of ending their drive to divide Sarajevo, fighting in sporadic clashes Wednesday with its predominantly Muslim Slav defense force as their artillery pumped intermittent rounds into the city.

"Serbian sniper bullets are flying through our apartments," said a resident by telephone from Dobrinja, a residential settlement on the western fringe of Sarajevo that Serbian forces have been battling for weeks to capture.

The fighting prevented the distribution of at least five plane loads of humanitarian relief supplies that arrived at the airport in the two days since Serbian forces relinquished control of the facility. US presence condemned

In Belgrade, the American military presence in the Adriatic was condemned by the state-run news agency Tanjug, which also criticized the silence of the officialdom of rump Yugoslavia, the Serb-dominated union forged by Serbia and its tiny prot, Montenegro.

The first measure of how effective the US policy will be could come this weekend when Lord Peter Carrington, the British chairman of the EC-sponsored negotiations on the Yugoslav crisis, has said he wants to visit Sarajevo to resume peace talks.

Serbian leaders, as well as their Muslim Slav and Croat counterparts, appear ready to take serious steps toward ending the brutal conflict so foreign military intervention may be averted.

But should the carnage continue, the US could become involved in a European conflict for the first time since the end of World War II almost a half century ago.