ZAGREB, CROATIA — A NEW upsurge in fighting threatens to plunge Bosnia-Herzegovina back into all-out war and has dampened already bleak hopes for what is being seen as a final attempt by the world's great powers to broker a peace accord.
``It's difficult to see any optimistic scenario,'' a senior United Nations official says. ``If the peace initiative collapses, the international community will not be prepared to make another.''
Should the worst happen, some Western diplomats and UN officials fear a pullout or crippling reduction of UN peacekeeping forces amid a resumption of wholesale mayhem.
Such fighting, they say, could then spread into adjacent Croatia, where peace talks between the government and minority Serb rebels holding almost a third of the country have been deadlocked for months.
``The longer it takes to solve Bosnia, the longer it takes to solve the other problems, and the more chance there is of a repetition of war in Croatia,'' a UN official warns.
Fighting in Bosnia had lapsed in the first days of a month-long cease-fire that the Bosnian Serbs and the new Muslim-Croat federation agreed to begin observing on June 10.
But the truce went the way of its numerous predecessors when the Muslim-dominated Bosnian Army launched an offensive late last week around the north-central Bosnian Serb-held city of Doboj and the adjacent finger-shaped Mount Ozren region.
The apparent goal is to secure a road that cuts through the southern end of the Mount Ozren pocket and links the key Muslim strongholds of Tuzla and Zenica, UN officials say.
Its capture would give the Bosnian Army an all-weather route by which to transport food and arms supplies to Tuzla from Croatia's Adriatic coast.
Hundreds of Bosnian Serb civilians have fled as Bosnian forces advance along the road from the east and west, the officials say.
Serbs haven't retaliated yet
UN officials are surprised that Bosnian Serb leader Radovan Karadzic has not retaliated. ``That's what we still fear,'' says one UN official.
To control the road, a senior UN military commander explains, the Bosnian Army will have to push deep into the Ozren region, a pure Serbian enclave, to eliminate the threat of long-range artillery attacks, and that could prove too much for Mr. Karadzic.
UN officials say concerns that the Mount Ozren fighting and cease-fire breaches elsewhere presage a return to full-scale war are rooted in the new strength of Bosnia's Muslim forces and their political leaders in Sarajevo.
Since the United States-sponsored Muslim-Croat reconciliation in January, Muslim troops no longer have to fight on two fronts. NATO threats to launch airstrikes if the Bosnian Serbs attack Sarajevo or five other UN protected areas have also lessened their burden.
Consequently, tens of thousands of troops have been shifted to battle the Bosnian Serbs, bolstered by new arms supplies from Croatia, UN officials say. ``The Serb aggressor no longer has the strength to become more powerful, and the Bosnian Army has the power to begin a war of liberation,'' Bosnian Army commander Rasim Delic claimed over the weekend.
Many analysts dismiss such assertions as propaganda because of the Bosnian Serbs' superiority in heavy weaponry. But others say the infantry-rich Bosnian Army might be able to retake significant amounts of territory in a prolonged guerrilla war. ``I think they intend to recapture all of Bosnia, but over a long period of time,'' one UN official says.
The new developments bode badly for the latest international peace plan, the prospects of which are already bleak.
The so-called Contact Group of US, British, French, German, and Russian mediators is finalizing the third international peace plan of the more than two-year conflict. It would award 51 percent of Bosnia to the Muslim-Croat federation and the remainder to the Bosnian Serbs, whose Belgrade-bankrolled ``ethnic cleansing'' conquests have left them with 72 percent of the former Yugoslav republic.
The plan is to be presented for endorsement to Contact Group country foreign ministers in Geneva on July 1 or 2.
The Bosnian sides may be called to Geneva to receive the plan before it is presented to the heads of state of the world's leading industrial powers and Russia at the annual Group of Seven summit in Naples in early July.
Western officials have warned that the plan will be offered on a take-it-or-leave-it basis, with the prospects of an end to international mediation and unrelenting fighting intended to pressure the sides into agreeing to something that neither want.
Means of inducement
That and the plan's promotion by the world's most powerful leaders are among a number of inducement mechanisms.
Agreement by Karadzic and his patron, President Slobodan Milosevic of Serbia, could lead to a slackening of UN sanctions imposed on the rump Yugoslav union of Serbia and Montenegro in May 1992 for its role in the Bosnian Serb land-grab.
A Serb refusal could lead to tighter sanctions and an exemption for Sarajevo from a UN arms embargo. Conversely, the sanctions on Belgrade could be loosened if Sarajevo resists the new peace plan.
Finally, Britain and France are warning that a lack of progress in coming weeks could force them to withdraw troops that are the backbone of the world's biggest UN peacekeeping and humanitarian aid-delivery operation.
Despite all of the pressures, however, few analysts believe that the factions will make the compromises necessary for the plan to succeed.