Recent confrontations in Lebanon between United States marines and Israeli troops are causing concern here. Hence, in order to avoid the possibility of actual clashes, Israel has ordered its troops not to approach marine-controlled areas - even in hot pursuit of Arab guerrillas ambushing Israeli convoys.
Defense Minister Ariel Sharon notified US Ambassador to Israel Samuel Lewis of this policy in a meeting last week. Official Israeli sources expressed astonishment at a statement by US Defense Secretary Caspar Weinberger on American television over the weekend that he was ''very worried'' that the recent incidents involving the marines and Israeli troops could ''grow into something much more serious.''
Israeli defense officials termed Mr. Weinberger's remarks an ''overreaction.'' They say that they seemed to indicate a desire in Washington to make an issue over a marginal matter on which Israel has already backed off.
Jerusalem is acutely aware that any clash with the marines could undermine American suppport for Israel. The marines, together with French and Italian units, are part of the multinational peacekeeping force in Beirut.
(US special envoy Philip Habib returned to Jerusalem Sunday night amid indications that there were deep differences between Israel and the US over Israel's negotiations with Lebanon, according to the wire services. An Israeli official was reported as saying that Habib's lengthy discussions last week with Israeli ministers made no progress.)
The area in which the confrontations between marines and Israelis have occurred is just southeast of Beirut, adjacent to a road serving as a main artery for the Israeli forces in the area. There have been several Arab guerrilla ambushes of Israeli vehicles there in recent weeks. A major was killed and more than a dozen soldiers wounded in these incidents.
Israeli military sources say that tracks from the ambush point have led toward the Palestinian refugee camp Borj el Barajneh in south Beirut and adjacent neighborhoods. These areas are controlled by the Lebanese Army and the multinational force.
On Jan. 17 two Israeli jeeps on an anti-guerrilla patrol encountered a marine detachment in an area the Israelis contend is under Israeli control according to an agreement arrived at with US envoy Maurice Draper and the Lebanese Army. The marines, however, said they had no knowledge of such an agreement and amidst shouts of ''this is no drill'' raced to battle positions.
The Israelis withdrew without pressing the point - although the Americans contend that one of the jeeps ''nudged'' a marine. The Israelis say their troops were surprised at seeing the marines there and withdrew without any verbal exchange.
While avoiding direct contact with marines, the Israelis have stepped up patrols in the adjacent area and established observation points. These patrols include morning sweeps by armored personnel carriers which direct small-arms fire at possible ambush points such as thick brush. The Americans have complained that such fire has come uncomfortably close to the marine positions.
The unexpected presence of the marines has confronted the Israelis with an uncomfortable dilemma. Guerrillas have become increasingly bold in recent weeks in attacking Israeli vehicles in the Beirut area and the Israelis have adopted their active patrolling policy to thwart such moves. Israeli military sources say that in addition to the tracks leading from ambush points toward Beirut, guerrillas have been spotted fleeing into the city through the lines of the Lebanese Army and multinational force.