President Bush yesterday called Prime Minister Yitzhak Shamir to ask that Israel, in the words of a senior U.S. official, "lay low" and "stay out" of the Persian Gulf conflict.

Administration officials said Bush phoned Shamir to tell him he has dispatched Deputy Secretary of State Lawrence S. Eagleburger to Israel for discussions of the conflict and to ask that Israel not consider a preemptive strike against Iraq despite Iraq's announced intention to attack Israel if war erupts in the Persian Gulf. The message, said one official, was Israel should not "play into Saddam's hands" by turning the conflict into an Israel-Arab confrontation.

The White House took additional steps to prepare for military conflict, asking all Americans yesterday to leave Baghdad and arranging evacuations. Further, the Pentagon asked Bush for authority to extend for up to two years the service of military reservists who have been called to active duty as a result of the gulf crisis.

Senior officials in private and public continued to hold out virtually no hope for a diplomatic solution to the crisis, while still encouraging efforts by third parties, such as United Nations Secretary General Javier Perez de Cuellar, to try to persuade Saddam to withdraw from Kuwait.

A senior official said Perez de Cuellar, in two phone conversations with Bush on his mission to Baghdad, was not hopeful he could achieve any breakthrough with the Iraqi leader. The official said "nobody has given him {Perez de Cuellar} a new mandate," saying the mission remains trying to persuade Saddam to withdraw unconditionally. This official and others insisted there was no secret diplomacy, no new offer involved in the U.N. effort.

White House press secretary Marlin Fitzwater described the mood in the White House as "somber," adding that "everyone is concerned about time running out." The administration's goal over the next five days until the Jan. 15 deadline set by the U.N. Security Council is "to do nothing or say nothing that gives Saddam any opening to think we are any less than 1,000 percent steadfast and certain about what our course of action is," Fitzwater said.

The Eagleburger mission comes in the wake of statements by Iraqi Foreign Minister Tariq Aziz, following his meeting Wednesday with Secretary of State James A. Baker III in Geneva, that if war breaks out after expiration of next week's deadline, Iraq unhesitatingly will strike at Israel.

Aziz did not elaborate, but the expectation is that Iraq would use its Soviet-made Scud missiles, possibly armed with chemical warfare agents, to hit Israeli cities. U.S. planners are understood to have targeted these missiles for destruction at the outset of any war.

Answering questions yesterday about what the United States would do if Iraq actually attacks Israel, Fitzwater said: "We have always said that should Iraq move against any other country, that we would respond. So that policy has not changed."

Eagleburger is to reiterate Bush's plea for Israel to be patient in the face of provocative statements by Iraq and to maintain the low profile it has tried to keep since the outset of the gulf crisis.

Fitzwater would not say yesterday whether Bush had asked Shamir to refrain from striking first against Iraq, but senior officials said that was part of his message. Earlier yesterday, Rep. Les Aspin (D-Wis.), chairman of the House Armed Services Committee, said at a breakfast meeting with reporters that the Shamir government had agreed not to make any preemptive strikes and, if it does come under attack by Iraqi forces, to make only limited retaliations.

"It would be an eye-for-an-eye retaliation, or, given the Israelis, probably two eyes for an eye," Aspin said. "That the Arab {allies} can live with. They don't want Israel in the war on a daily basis."

According to Aspin, the biggest potential problem would arise if Saddam launched a preemptive strike against Israel before other hostilities began. The United States would have to intervene, he said, but the Arab members of the international coalition against Iraq would find it very difficult to join in a fight between Israel and Iraq.

The Bush administration, meanwhile, yesterday urged all Americans still in Iraq to leave. At the State Department, spokesman Richard Boucher said the U.S. Embassy in Baghdad is contacting the approximately 180 private American citizens it estimates are still in Iraq to determine whether any of them wish to leave the country. Baker was given assurances by Aziz in Geneva that the embassy staff can depart Iraq on a charter flight Saturday, and Boucher said any of the private Americans who have exit permits also will be able to leave on that flight.

Boucher added that so far only one family, which he described as an American-born child and three foreign-born relatives, has said it wants to leave. Almost all of the U.S. citizens still in Iraq have dual nationality and up to now have said they wish to remain or, in some cases, have been unable to obtain exit permits because Iraq considers them Iraqi citizens.

The estimate of 180 Americans includes journalists temporarily in Iraq to cover the gulf crisis, and Fitzwater stressed that the call for all Americans to leave includes them.

Boucher said that despite the departure of U.S. officials, the United States does not intend at this time to sever diplomatic relations with Iraq. As a result, he said, the embassy technically will remain open.

The department also announced that it is reducing its embassy staff in Yemen, an Arab gulf state that has shown sympathy for Iraq, and has advised the U.S. embassies in Algeria, Tunisia and Morocco to evacuate dependents and non-essential personnel. It also urged private American citizens to suspend non-essential travel to these countries.

No explanations were given for singling out these countries, but public opinion in all is strongly pro-Iraqi. Algeria's ruling National Liberation Front has announced plans for massive anti-war demonstrations if war breaks out, and Tunisia is the headquarters of the Palestine Liberation Organization, Iraq's strongest source of support in the Arab world.