Paris — The French are the only peacekeeping nation not yet withdrawing from Beirut - but they are frantically looking for a way out. Officially, the government of President Francois Mitterrand is keeping its 1, 200 troops in place while stepping up its efforts to install a United Nations force in the Lebanese capital.
But privately, top French officials interviewed by the Monitor doubt that this force can be created. They suggest the French soldiers, too, will soon have to withdraw.
''We can't do it all by ourselves,'' an official said. ''We'll probably have to withdraw.''
The French are also frustrated by the UN option. Officials note that ever since the multinational peacekeeping force was put together in August l982, Paris has pushed for a UN force as a way of increasing the international legitimacy of the peacekeepers.
The French say the Reagan administration blocked the idea, fearing it would give the Soviet Union too much leverage in the Middle East. At this late date the French still hope the Americans will drop their opposition. But even then, the question is how the Soviets will respond.
In recent talks between the secretary-general of the French Foreign Ministry, Francois Gutman, and Politburo officials, the Soviets did not say ''nyet'' to French ideas for a UN force in Lebanon.
Instead of repeating their official line against an increase in the number of peacekeeping troops in Lebanon, the Soviets asked questions about a new force's role. Some officials here take this as a signal of potential Soviet willingness to cooperate.
But most officials are skeptical that this will translate into approval for the force. They suggest it may merely represent a Soviet effort to create tension in the Western alliance. More important, they realize the quid pro quo for Soviet acceptance will be high.
''Three weeks ago, the Soviet demands might have been reasonable,'' an official explains. ''But now they are certain to raise the ante a lot.''
So what to do? The French seem at a loss to give a clear answer. At present, they hope their troops can stay in Lebanon without suffering too many casualties.
''We still have lots of contacts with the Lebanese Muslims,'' particularly Druze leader Walid Jumblatt and moderate Shiite leader Nabih Berri, an official said. ''We are less identified with the Gemayal government than the Americans - and this will make a difference.''
Separating themselves from the US may, in fact, be the major reason the French are staying on. It also explains why officials here do not seem at all upset by the US failure to consult Paris before making its withdrawal decision. The French were notified just before the decision was made public.
As their troops hang on, the French hope the Syrians will restrain their Lebanese clients. The secular regime in Damascus may not want the Lebanese Muslims to get too powerful, fearing that Lebanon could eventually become a grave threat by being transformed into a fundamentalist Iranian-style state.
In addition, the French speculate that the Soviets may have given the green light for the new violence - perhaps in retaliation for American deployment of the Pershing II missiles in Europe - but that now with the Americans embarrassed , they may figure it is time to restrain their allies and calm the game.
''We all know World War III could start in the Middle East,'' one official said. ''And we don't think the Soviets want the crisis to escalate.''
This does not mean the French are optimistic about the situation in Beirut. Officials offer a full spectrum of pessimistic scenarios that range from a military coup to President Amin Gemayel's assassination to anarchy.
But in the long term, the French believe the Syrian victory will turn out to be limited. They see the Syrian regime as inherently unstable.