THE diplomatic quest for peace in the former Yugoslavia is about to move to Geneva, following what a senior United Nations official called "the striking success" of last week's London conference on the Balkan crisis.
The official said that beginning Thursday, and "building on the momentum achieved in London," a number of committees under the joint auspices of the UN and the European Community will monitor commitments made in London by leaders of the ex-Yugoslav delegations to work for a cease-fire and to respect frontiers.
Cochaired by former US Secretary of State Cyrus Vance and Lord Owen, the European Community's newly appointed mediator, the committees, meeting in permanent session, also will discuss the political and constitutional future of Bosnia.
They will do so amid a widespread belief that the London talks produced a framework for peace which will require a huge amount of goodwill on all sides to end the fighting.
Further progress in the peace process, British sources said yesterday, would probably also depend on UN and EC success in attempts to tighten up sanctions against Serbia.
"Serbia is getting oil and other vital supplies being sent in along the River Danube," the source said, "and that must stop."
As if to underline the fragility of what was achieved in London, guns and rocket launchers sounded off around the besieged city of Sarajevo and elsewhere in Bosnia throughout the weekend.
On Friday British Prime Minister John Major forecast that the Geneva sessions would be "long and probably difficult."
"The fighting will not stop immediately. The problem is far too complicated for that to be possible," added Mr. Major, who co-chaired the London talks with UN Secretary-General Boutros Boutros-Ghali.
Mr. Boutros-Ghali told a news conference that "months, possibly years of effort" would be needed to restore the former Yugoslavia to stability and peace.
Lord Owen, a former British foreign secretary, planned to leave London today for a swift tour of European capitals before going to Geneva to meet Mr. Vance. He will consult EC governments as fully as possible about their views on the crisis.
"We are entering a new phase," a source close to Owen says. "For the first time UN and EC peace efforts are being brought under a single umbrella. The agreements signed by the participants at the London talks give us an agenda to work on."
"Lord Owen knows as well as anyone that there have been many disappointments as cease-fire agreements were broken," he says.
"This time the combatants have made commitments in the presence of virtually the entire world community, and they know that sanctions will be tightened against them if those commitments are broken."
One of the key promises made in London was by Radovan Karadzic, leader of the Bosnian Serbs, who said he would allow UN monitors to locate and supervise heavy weapons stationed near the besieged towns of Sarajevo, Gorazde, Bihac, and Jajce.
On Saturday Dr. Karadzic announced the withdrawal of 1,000 Serb irregulars from Gorazde, saying this was "in accordance with our obligations undertaken at the London conference."
Yesterday Bosnia claimed to have retaken control of the town.
At the end of the London talks Karadzic said he was willing to hand back to Muslims "up to 20 percent of the territory" seized by Serbs in Bosnia.
In reality, the British government says that this may be an opening gambit in a long and acrimonious wrangle over territory. British officials estimate that 75 percent of Bosnia is now under Serbian control.
This gives Karadzic a strong bargaining position in Geneva," says Jonathan Eyal, director of the London-based Royal United Service Institute.
Dr. Eyal, a specialist on Balkan politics, forecast that the Bosnian Serbs would resist attempts to make them give up land they have seized, even though Karadzic had given the London conference binding agreements in this regard.
"Part of the problem is that no one really knows how much authority Dr. Karadzic has over Serbian irregulars," Eyal says.
Yesterday Prime Minister Major received a letter from Karadzic complaining of a "crazed onslaught" by Muslim forces in Sarajevo and demanding that Britain require Muslim forces to "show restraint."
At the weekend Muslim forces on the northern perimeter of Sarajevo, in an apparent attempt to lift the siege of the city, were reported to have launched an attack on Serbian positions.
The Geneva sessions will put pressure on the Serbs to honor their promises on UN monitoring of their heavy weapons, but getting this process into gear promises to be slow and difficult.
UN under-secretary for peacekeeping operations, Marrack Goulding, flew to Bosnia over the weekend to begin locating the weapons.
His visit marks the opening move in attempts to bring heavy weapons under international control, a UN official says. "We have had promises about the monitoring of weapons in the past, and our experience has not been encouraging."