Israel's Cabinet today accepted the troop withdrawal agreement with Lebanon that was hammered out with the help of Secretary of State George P. Shultz, voting to approve it "in principle" but calling for clarifications on some security and political issues.

Israeli officials and Shultz said, however, that the clarifications should pose no serious roadblock to signing of the accord, which Lebanon already has approved.

While approval of the agreement is considered by the countries involved to be a major diplomatic achievement, the actual withdrawal of the 30,000-man Israeli force that invaded Lebanon 11 months ago today will not take place until Syria and the Palestine Liberation Organization also agree to remove their forces.

Syria's state-controlled radio strongly condemned the Lebanese-Israeli agreement before the Cabinet vote today, but there was no official reaction. Shultz, who left Jerusalem late today for talks with Jordan's King Hussein in Amman, is scheduled to go to Damascus Saturday in an attempt to win Syrian support for a negotiated withdrawal of all foreign forces from Lebanon.

President Reagan, speaking in Phoenix, hailed Israel's approval of the agreement, calling it "a step forward" that "can lead to the restoration of Lebanon's sovereignty throughout its territory while also ensuring that southern Lebanon will not again become a base for hostile actions against Israel."

Shultz, while flying to Amman, hinted to reporters that Reagan, as part of the U.S. effort to win Israeli support for the agreement, may have decided to lift the embargo that he imposed earlier this year on the delivery of F16 fighter planes to Israel, Washington Post staff writer John M. Goshko reported.

In Beirut, Lebanese officials gave a guarded welcome to Israel's approval, with a top adviser to President Amin Gemayel saying, "We want to know what the clarifications are." Earlier, Gemayel told a military gathering, "We will not back off from concluding any agreement that would ensure our independence and liberate our land without giving up one iota of Lebanese sovereignty or honor."

The Soviet Union, a close ally of Syria, attacked the agreement, with the official news agency Tass calling it a joint move by Israel and the United States "to impose upon Lebanon a capitulatory and shackling plan of enslaving the Lebanese and the Palestinians," The Associated Press reported from Moscow.

The Israeli Cabinet's 17-to-2 vote to approve the troop withdrawal agreement followed more than five months of intensive U.S. diplomatic efforts, including lengthy mediation efforts by special envoy Philip C. Habib and, in the past 12 days, the shuttle diplomacy of Shultz who was sent to the Middle East by Reagan to wrap up the final accord.

The agreement, which has not been made public, provides for both the withdrawal of the Israeli military force that invaded Lebanon last June and greater security for Israel's northern border with Lebanon.

The Cabinet approved the agreement after a seven-hour debate that was described as "very difficult" and was said to have taken place in a "heavy atmosphere." The two who voted against it were former defense minister Ariel Sharon, the architect of the invasion of Lebanon, and Science Minister Yuval Neeman, a member of the right-wing Tehiya Party.

The Cabinet said in a statement that it had "decided to approve in principle the proposed agreement between Israel and Lebanon. Regarding a number of security and political problems, the government will act to receive further clarifications."

Israeli officials refused to say what steps would be taken if Syria does not agree to withdraw, but some Cabinet ministers said they would favor a unilateral Israeli withdrawal to a smaller and more defensible area of southern Lebanon, where the Israeli Army would be in a better position to wait out the Syrians, however long it took. Syria's 40,000 to 50,000 troops are largely in the Bekaa Valley, with the estimated 6,000 PLO forces both there and in northern Lebanon.

It was understood that the most sensitive portions of the agreement will remain secret even after much of the text is published. Some of the most controversial issues, including the role of Saad Haddad, a former Lebanese Army major long allied with Israel, and the operational powers of Israeli soldiers who will continue to help supervise a proposed security zone in southern Lebanon, are to be set out in documents separate from the main agreement.

Israeli officials would not say what clarifications they are seeking. One may involve U.S.-built F16 warplanes, whose delivery to Israel has been linked by Reagan to a troop withdrawal. Israel reportedly is seeking assurances, if it has not already received them, that the embargo will be lifted upon signing of the agreement with Lebanon and will not hinge on an actual troop pullout that is contingent on the Syrians.

When reporters traveling with Shultz to Amman asked if the F16s--whose delivery actually is not due until 1985--will now be released to Israel, Shultz replied:

"I'm not going to scoop the president, but I don't see any reason why . . . ." At that point he broke off and said, "I'm going to stop right there. I'm not going to scoop the president."

Israeli radio said two of the clarifications being sought involve Haddad's status and what recourse Israel will have if the security arrangements in southern Lebanon break down.

Informed sources said the agreement calls for two separate security zones in southern Lebanon. The first, extending about 10 miles north of the Israeli border, would be manned by Haddad's Israeli-supported militia, which is to be made a part of the Lebanese Army. The territory corresponds roughly to that which has been under the control of Haddad's forces since the mid-1970s.

The northern portion of the security zone, extending to the Awali River, is to be patrolled by the Lebanese Army. U.N. troops, whose continued presence in Lebanon Israel strongly opposed, were said to be given a role in the agreement in the coastal road area between Tyre and Sidon where two large Palestinian refugee camps are located. Their main purpose would be to provide a military presence near the camps.

Haddad, according to several reports, is to be named "deputy commander" of the entire security area with special responsibility for intelligence and antiterrorist activities.

Israel and Lebanon also agreed to a mechanism for the security zone to be supervised by joint teams made up of soldiers from both countries, but the details were not made known.

Sharon, in a statement after the Cabinet meeting, said he opposed the agreement because it did not satisfy Israel's security needs and did an "injustice" to Haddad. But Cabinet Secretary Dan Meridor told reporters, "Israel has not let down Maj. Haddad."

The agreement also calls for an end to the formal state of war between Israel and Lebanon, pledges both countries to refrain from hostile propaganda and to respect each other's sovereignty and territorial integrity and states that negotiations on establishing mutual relations will begin six months after a troop withdrawal.

Meridor and Begin's spokesman, Uri Porat, voiced to reporters the argument that Begin and Defense Minister Moshe Arens made during the Cabinet meeting to overcome Sharon's objections and the reluctance of several other ministers to accept the accord.

"Taking into account the situation in Lebanon, I think this is the most we could achieve now," Meridor said.

"It is not so bad an agreement," Porat added. "This was the best we could achieve."

Israel's willingness to accept what officials here said was far less than sought was influenced by the continued instability of Lebanon, where more than 130 Israeli soldiers have been killed since the formal end of hostilities in September.

Goshko added the following from Amman:

During the flight from Jerusalem to Amman, Shultz told reporters that the clarifications sought by Israel "will not pose any real problems. I think they can all be taken care of." He added, "I say that on the basis of a very brief conversation."

A senior U.S. official accompanying Shultz said that Samuel Lewis, the U.S. ambassador to Israel, was dealing with the Israelis on the clarifications and that it was the U.S. understanding that they "already are virtually all taken care of."

Shultz also said the United States had given Israel "a letter of assurances" relating to the agreement. "It says a variety of things," he said, but did not elaborate.

He said it was not certain when the agreement will be signed, but he indicated that it would be done by the negotiating groups that had worked on the withdrawal issue. That would be a victory for Lebanon, which wanted the signing to be done by relatively low-ranking officials rather than by foreign ministers, as Israel had demanded.

Upon arrival in Amman, Shultz was greeted by Jordanian Foreign Minister Marwan Kasim, who said, "What we have heard a short while ago about the Israeli-Lebanese agreement is indeed a very positive development. We hope it will contribute to an overall settlement in the region."

Special correspondent Nora Boustany reported from Beirut:

Gemayel, speaking at a graduation ceremony for cadet officers a few hours before the Israeli Cabinet vote, thanked the United States and Reagan for their participation and support of Lebanon in the negotiations.

One of Gemayel's top advisers said that "we want to know that the clarifications are," but added, "We are prepared to stand by the agreement, and we hope this will be the start of a new era."

Political observers here noted that skepticism will prevail pending the outcome of Shultz's visit to Syria.

Meanwhile, shelling continued between Christian and Moslem Druze forces in the mountains outside Beirut, but observers said it had tapered off from the intense duels of the past two days, when Beirut and its suburbs came under fire.

[Israel's military command said one of several soldiers who were encircled by a stone-throwing crowd shot and killed a youth and wounded seven others in the southern Lebanese town of Tyre, United Press International reported.]