DAMASCUS, SYRIA, FEB. 27 -- Syria and Jordan today publicly rejected key elements of the new American approach to reviving the Middle East peace process, insisting upon a U.N.-sponsored international conference that Israeli Prime Minister Yitzhak Shamir has already rebuffed.

Syrian President Hafez Assad listened "closely" to Shultz's "ideas" during almost three hours of talks, Syrian Foreign Minister Farouk Charaa said. But, Charaa added bluntly, "no agreement was reached."

"We believe the solution can be best dealt with through the convening of an international conference under United Nations auspices, where the permanent members of the Security Council and the parties concerned, including the PLO {Palestine Liberation Organization}, will participate."

Charaa also said that Syria believed that "partial and unilateral solutions would only complicate the situation rather than solving it." He was apparently referring to the new U.S. plan, which calls first for negotiations on limited Palestinian autonomy in the Israeli-occupied West Bank and Gaza Strip before the start of talks on their final status six months later.

The plan also envisages an "international event" at the start of negotiations, but Shultz has made it clear now that he opposes a full-fledged conference under U.N. auspices. In addition, he has always rejected PLO participation until it renounces terrorism and recognizes Israel.

{At least two more young Palestinian men were killed by Israeli gunfire on the West Bank and a number were wounded, correspondent Edward Cody reported from Jerusalem. The deaths brought to 69 the number of Palestinians confirmed killed by Israeli gunfire and beatings since the West Bank and Gaza uprising began in early December.

{The killings occurred as Israeli soldiers broke up crowds seeking to prevent cars from passing on the road between Bethlehem and Hebron, Israeli and Palestinian sources said. The Army reported that troops sought to disperse the rock-throwing youths with rubber bullets and tear gas but twice opened fire when crowds refused to back away.

{After the violence, soldiers imposed a curfew on towns and villages lying along the road from Hebron as far north as the Jewish settlement of Etzion, near Bethlehem. Israeli radio said Israelis were being allowed to pass along that stretch of the road, but not Palestinians.

{One 17-year-old was killed at Halhoul, just north of Hebron, and the second youth, 21, was killed at the Arub refugee camp just south of Bethlehem, the Army reported. The Associated Press quoted hospital officials in Jerusalem as saying that a second teen-ager from Halhoul had died from Army gunfire.}

Earlier today, after Shultz held another three hours of talks with Jordan's Prime Minister Zaid Rifai in Amman, Jordanian Foreign Minister Tahir Masri called for a U.N. conference in a statement worded almost identically to that of Syria, suggesting that the two governments had coordinated their stands toward the Shultz plan.

The secretary, after listening to Charaa's declaration here, said, "Let me underline what the foreign minister said. We did not reach any agreement."

Nonetheless, Charaa said the two sides had agreed to continue exploring "the best way to arrive at a comprehensive solution."

A Shultz aide said Assistant Secretary of State Richard W. Murphy would return to Damascus while Shultz is attending a NATO summit in Brussels March 2-3. He hinted that Shultz may return to the region after that meeting.

Despite the formal insistence by Syrian and Jordanian leaders on the holding of an international conference with the PLO in attendance, Shultz did not seem discouraged. There was a sense that all parties, including Shamir, were presenting their opening positions at the start of long, hard bargaining.

Talking to reporters aboard his plane late tonight on the way back to Tel Aviv, Shultz seemed in surprisingly good humor and undaunted by the day's apparently discouraging talks in Amman and Damascus.

Asked if he had seen any progress, Shultz replied, "I'm overwhelmed by your sense of humor."

"The idea in negotiations of this kind," he said philosophically, "is to get people to be realistic. We're not there yet."

However, a senior official noted that "nobody is saying no" to Shultz so far. "That's what makes them so mad. There is no other game in town and they know it."

"Assad," he said, "in effect told Shultz, 'Come back and talk to me some more.' "

The official said that, at one point during his meeting with Assad, Shultz had sought to clarify his complicated peace plan by diagramming on paper how all the parts would fit together.

Shultz's aides also said that the Jordanians had expressed far more interest in the U.S. plan in private than their formal statement suggested. The secretary indicated as much today, saying that Jordan's formal statement had only expressed "some elements" of the overall Jordanian viewpoint.

Shultz was unable to meet King Hussein, who is in London for medical treatment. Shultz plans to fly there Tuesday in order to discuss his peace plan with Hussein.

Two days of talks with Israeli and Arab leaders have made it clear that Shultz faces a difficult job in his effort to revive the moribund peace process.

He is trying to reconcile Arab demands, for a U.N. conference and for a firm date for the start of final-status talks, with Shamir's insistence that there be no such conference and a fixed period of limited Palestinian autonomy before the final negotiations begin.

The Arab side fears that Shamir will stop at limited autonomy and never go on to final status negotiations on the basis of "land for peace" as the Americans are demanding. Shamir, on the other hand, is fearful that if the Arab side knows the final settlement talks are certain to start by December, as Shultz is suggesting, it will never take the autonomy talks seriously.

The senior U.S. official suggested today that Shamir was already beginning to show some flexibility by "reluctantly" accepting the idea of an "international event" at the start of negotiations. But he conceded that Shamir's idea of such an event was still far apart from the Arab concept of a U.N.-sponsored peace conference.

The official said Shultz is prepared to keep searching for a compromise so long as he believe that there is some chance of success.

On Sunday, Shultz plans to meet first with Shamir again and then fly to Cairo for talks with President Hosni Mubarak. On Monday, he is scheduled to go back to Amman for more talks with Jordanian officials as well as to hold meetings in Jerusalem with both Shamir and Israeli Foreign Minister Shimon Peres.