PARIS — WHILE Bosnian Serbs move to the endgame on the remaining five Muslim ''safe zones'' in Bosnia, Western leaders are giving themselves a week to determine how - or whether - to make a stand.
The fall of the United Nations safe zone of Srebrenica last week and the threat to a second zone at Zepa - a town of 16,000 some 30 miles east of Sarajevo - set off renewed posturing among Western powers and talks on the collapsing UN peacekeeping mission.
On Sunday, American, British, and French military chiefs met in London to discuss French proposals to reinforce the remaining safe zones. This Friday, the ''contact group'' on Bosnia - the United States, Britain, France, Russia, and Germany - is expected to meet in London to decide what to do. Both British and French officials insist Friday is not too late to take action in Bosnia, but reports of atrocities against tens of thousands of fleeing Bosnian Muslims suggest that for them, time is running out.
Details of the military consultations have been secret, but French officials confirm that their proposal includes:
* Reinforcing the safe zone of Gorazde by deploying a multinational Rapid Reaction Force, made up of French, British, and Dutch forces. France will ask for US helicopters to transport troops to Gorazde.
* Guaranteeing access to the Bosnian capital of Sarajevo.
''This is the decisive week,'' says Dominique Moisi of the Paris-based French Institute of International Relations. ''Either the West gets involved, with the chance of directly fighting the Serbs of Bosnia, or we all leave, arms come to the Bosnians, the war escalates, and we're in a totally different ballgame.''
Both US and British officials express doubts over the French proposals. The US supported efforts to preserve the three remaining safe zones, but did not commit to supplying helicopters.
''Helicopters are ground forces,'' says a US official. ''It's a very different sort of cooperation than we've been asked to provide up to this point, such as enforcing no-fly zones. We need to be very clear in cooperation with the allies as to just what this operation would involve from the US.''
Senate majority leader Bob Dole (R) of Kansas plans to call a Senate vote this week to lift the arms embargo on Bosnia. If the vote passes, it would effectively end UN peacekeeping there.
British officials have been in contact with the French to discuss options for ground forces. ''We will consider any realistic plan,'' says a spokesman for Britain's ministry of defense. ''But we have to ensure that we can deploy our young soldiers on realistic operations that can really be achieved.''
France has stepped back from what first appeared to be a unilateral offer to deploy troops to retake Srebrenica. But French President Jacques Chirac has not yielded one inch of the moral high ground he claimed last week.
''Let us not forget that the values that founded our democracies are being mocked in Europe itself and most notably in Bosnia, right under our own eyes, by practitioners of ethnic purification,'' President Chirac said Sunday. ''We must not accept being passive witnesses or accomplices of the unacceptable.''
Chirac spoke at a commemoration of the 53rd anniversary of the first mass arrests to deport 76,000 Jews to Nazi death camps. It was the first time a French head of state admitted French government responsibility for these deportations.
THE comparison of Bosnian Serbs to Nazis escalates the war of words over Bosnia. Chirac compared the West's response to the fall of UN safe zones to ''appeasement'' talks before Germany invaded Czechoslovakia in 1938. Britain did not welcome the comparison, saying French policy has been the same as Britian's for two years.
France and Britain have provided most of the peacekeepers that make up the 15,000-member UN force in Bosnia. Both oppose lifting the arms embargo in Bosnia. And both supported the creation of a Rapid Reaction Force after some 370 peacekeepers were seized by Bosnian Serbs in May. French officials deny a New York Times report that they brokered a deal with the Serbs involving easing off air strikes in return for release of hostages.
France's new president is eager to avoid even the appearance of accommodating Bosnia's Serbs, and the foreign service is picking up his strident tone. ''We are in front of a form of fascism. We must react and not yield to barbarism,'' said a French foreign ministry spokesman yesterday. ''The idea isn't to disagree with our partners, but to manifest our determination.''
Analysts say it is too early to tell whether tougher talk in Paris will lead to stronger action. ''We have a new French president who wants to make an impact,'' says Mr. Moisi. ''With Chirac, there is always some mystery. Is he more cynical than anyone else? Is this stepped up rhetoric just a signal to the French that he did his best, a convenient moral alibi to get out? It may be the end result, but I don't think it's his intention.''