June 12, 1982

Western diplomats said tonight that the cease-fire in effect between Syrian and Israeli forces was an ''extremely fragile'' arrangement. In the view of diplomats here, the last two days of fighting may have convinced Israel that the invasion was no longer the surgical operation that it had intended. Israeli losses were mounting, its advance was slowing and criticism was growing abroad and at home, the diplomats said. As late as Thursday, they said, Israeli commanders threatened to move into Beirut and advance to the strategic Beirut-Damascus highway. The Israeli Cabinet's decision to proclaim a cease-fire was apparently made very quickly this morning, according to the diplomats.

Israeli forces and Palestinian guerrillas fought throughout today on the approaches to Beirut and elsewhere in Lebanon as spokesmen for both said the newly proclaimed cease-fires of Israel and Syria did not apply to them. Israeli planes struck a heavy blow at the guerrillas when their bombs scored a direct hit on an apartment building here housing the military command offices of the Palestine Liberation Organization. The building collapsed, reportedly trapping some P.L.O. officials in an underground bunker, but the top leaders were said to have escaped injury. A P.L.O. statement said that more than 100 people had been killed, most of them civilians.

The Reagan Administration has apparently decided to make the best of Israel's military moves in Lebanon by trying to translate them into a long-term political solution for Lebanon. In part, State Department officials said, this course was dictated when Prime Minister Menachem Begin told President Reagan on Thursday that he would agree to a cease-fire but would not pull Israeli forces out until certain conditions were met -namely, the creation of a Lebanese government free of Syrian and Palestine Liberation Organization pressure and the ending of the use of Lebanese territory as a military base for attacks on Israel. Officials said Middle East experts advised Secretary of State Alexander M. Haig Jr. that, because Mr. Begin was adamant, there was no way the United States could obtain an Israeli withdrawal except as part of an overall settlement of the Lebanese crisis. As a result, the Administration decided to welcome Israel's announcement today of a cease-fire and not to make an issue of Israel's refusal to accept the United Nations Security Council demand for an immediate withdrawal.

The Commerce Department announced today that it would levy stiff penalties on steel imports from nine countries, including seven in the European Common Market - an action that seemed certain to bring retaliation against American goods exported to Europe. The Commerce Department's action, if it is upheld on review, would result in the severest and widest application ever of duties against imported steel, a controversial issue for two decades. Common Market officials said that much of the affected steel - representing 4 percent of American steel consumption last year - would be priced out of the market. They said that they would retaliate by imposing similar duties on American exports whose manufacturers are helped with tax benefits and other subsidies from the United States Government.

Israel and Syria announced cease-fires in Lebanon today after a series of fierce tank, artillery and air battles. The truce, which took effect at noon (6 A.M., New York time), did not extend to the Palestinian guerrillas in Lebanon, Defense Minister Ariel Sharon said. The remaining military effort, he said, will concentrate on ''mopping up, cleaning'' a security zone reaching 25 miles into southern Lebanon north of the Israeli border. ''We have to search every cave and every wadi and all subterranean installations the terrorists built,'' Mr. Sharon said at a news conference. Fighting between Israeli and Palestinian forces was reported to be continuing near Beirut tonight, but Syrian-Israeli clashes appeared to have ended, with the cease-fire reported holding into the night.