Beirut — After two weeks, the fighting in Lebanon seems, for the moment at least, to have been contained. And although both France and the United States have made much-publicized efforts to bring about a cease-fire, the key role in containing the fighting appears to have been played by Saudi Arabia.
The Saudis, it now is said, contributed significantly to lowering the combativeness of the right-wing Christian Lebanese militias. They meanwhile had the same effect on the militias' opponents of the past three years, the Syrian troops of the Arab Deterrent Force (ADF) in Lebanon. They did this by signaling that the ADF mandate here may be near an end.
The Saudis' new appearance as active, not just behind-the-scenes, diplomats in the region dates from the Islamic summit hosted by Saudi Arabia last January.
Here in Beirut, the normally ebullient local motorists were venturing over the week-end to circulate cautiously within (but not yet between) the two sides of the divided capital. Both sides had previously been exposed to intermittent and fairly indiscriminate artillery shelling.
The fighting in Beirut and around the eastern town of Zahle killed an estimated 250 people on both sides of the line in the 10 days preceding the April 8 cease-fire between the Syrians and the right-wingers. The cease-fire has held with only some infractions in Zahle since then.
In southern Lebanon, meanwhile, Israeli commando attacks by land, sea, and air against alleged Palestinian guerrilla centers have continued, killing an estimated 60 Lebanese and Palestinians and destroying scores of dwellings.
The rhythm of Israeli-Palestinian confrontation in Lebanon and inside Israel may have its own momentum at a time when the "parliament-in-exile" of the Palestine Liberation Organization is in session. But in the Lebanese context, the net effect is further to destabilize the situation.
In Zahle, Red Cross teams were able to reach the worst-hit parts of the town on April 9. Some of the most severely injured residents were subsequently evacuated to France in two French hospital planes.
Considerable attention was focused here on such grand French gestures as this evacuation, the dispatch of a special envoy here by President Valery Giscard d'Estaing, and indications from the French foreign minister that France may take the Lebanese issue to the United Nations Security Council.
But in terms of actual diplomatic problemsolving, a greater role has been played by Saudi Arabia, which stamped on the ambitions of each of the combatants to the point where the April 18 cease-fire was possible.
On the right-wing side, there originally had been some hope that a hawkishly anti-Soviet United States and a friendly nearby Israel might provide the necessary backing for an all-out right-wing assault on the local troops of pro-Soviet Syria. These hopes were fueled by US Secretary of State Alexander M. Haig Jr., who, while in Israel near the beginning of his recent Mideast tour, denounced Syrian actions in Lebanon as "brutal."
But Syria's 20,000 troops in the ADF in Lebanon are here under a mandate from the Arab League supported by Saudi Arabia and all other league members. These states have believed, up to now, that the ADF presence has been the best guarantee that inter-Lebanese disputes lingering on since the 1975-76 civil war would not erupt again into the horrific fighting of those days.
The views of the Saudis and oterh Arab states on this score might be changing. But the current ADF mandate is good through July 25, so until then the mandate's sponsors must support the ADF as the major security force existing in Arab League-member Lebanon.
This point was brought home forcefully to Secretary Haig by his hosts during the Saudi Arabian leg of his Mideast tour.
Saudi sources here would confirm only informally that they have "reservations" about the val ue of extending the mandate after its present expiry date.