The United States began diplomatic soundings yesterday on the "new ideas" presented to President Reagan Tuesday by Arab foreign ministers for phased evacuation of Palestinian guerrillas from West Beirut.

U.S. special envoy Philip C. Habib met with Lebanese President Elias Sarkis in Beirut to present a report on the White House meeting and explore the ideas presented to Reagan by Saudi Arabian Foreign Minister Saud Faisal and Syrian Foreign Minister Abdal Halim Khaddam.

In Jerusalem, U.S. Ambassador Samuel Lewis performed much the same task in a meeting with Israeli Prime Minister Menachem Begin.

Although no definitive report was available in Washington late yesterday from either meeting, administration officials said they were prepared for negative initial reactions.

In anticipation, officials said, the two Arab ministers were asked by Reagan and Secretary of State George P. Shultz to provide more definite arrangements and commitments about when the Palestinians will leave Lebanon and where they will go.

Shultz left Washington yesterday afternoon for California, where he will play host to West German Chancellor Helmut Schmidt and Singapore Prime Minister Lee Kwan Yew at his home at Stanford University and at a weekend meeting of the exclusive, all-male Bohemian Club in a redwood grove north of San Francisco. Shultz will return to Washington late Monday.

The Middle East situation is likely to figure in some of the discussions, especially on Sunday, when Shultz, Schmidt and Lee are to be joined by former secretary of state Henry A. Kissinger for informal discussion about the problems of the world.

The Sunday meeting will be the second time in as many weekends that Shultz has sought the advice of Kissinger, who took part last Saturday in a lengthy and unusual brainstorming session on the Middle East at the State Department.

Despite speculation to the contrary, informed sources said there was little likelihood that Kissinger would be tapped as a special Middle East emissary. The emerging role for Kissinger, they said, seemed to be that of sounding board and outside adviser.

In the ideas presented to Reagan by the Arab foreign ministers, Palestine Liberation Organization fighters now trapped in West Beirut would make a first phase withdrawal to a temporary refuge in northern Lebanon. In the next phase, the fighters would depart from these temporary homes to new homes in several Arab countries.

The Arab League ambassador to the United States, Clovis Maksoud, said yesterday that the redeployment outside of Lebanon would require a credible international commitment to "Palestinian self-determination in their homeland." Otherwise, Maksoud said in a meeting with reporters, Palestinians would be entering a tunnel without a light at the end and, in effect, would court dispersion for the fourth time since leaving Palestine with no end to their wandering in sight.

The Arab foreign ministers, who were here as emissaries of the Arab League, made "suggestions" rather than clear proposals, according to Maksoud, because the ideas do not have the consent of all the parties.

Maksoud said a key Arab League committee of the PLO and five nations on the crisis in Lebanon is expected to meet Tuesday or Wednesday, following the traditional Islamic feast days for the end of the fast of Ramadan. More concrete decision-making about the Lebanon negotiations is a possibility at this meeting, the ambassador said.

According to Maksoud, the results of the Arab emissaries' meetings with Reagan and Shultz were "inadequate but positive." He said, "We didn't get from the United States a clear commitment on anything but there was a better awareness" and "greater sensitivity" to Arab concerns.

State Department spokesman Dean Fischer reiterated yesterday the unchanged U.S. position against direct dealings with the PLO until the organization in "clear and unequivocal" ways alters its position against recognizing the right of Israel to exist and two key United Nations resolutions.

Fischer said Hatem Hussaini, head of the PLO information office in Washington, was mistakenly admitted to a meeting last month of two West Bank mayors with Assistant Secretary of State Elliot Abrams. When the identity of Hussaini was uncovered, he was barred from meeting Assistant Secretary of State Nicholas Veliotes, Fischer said.