The Palestine Liberation Organization, shunting aside an appeal by King Hussein of Jordan for a change in its tactics and policies, reiterated today its rejection of U.N. Security Council Resolution 242 as a basis for Middle East peace negotiations.

The rejection came in a report to the 17th session of the Palestine National Council, the PLO's unofficial "parliament in exile," by Farouk Kaddoumi, director of the political department.

Kaddoumi endorsed Hussein's call for the formulation of a joint Jordanian-Palestinian position aimed at regaining the Israeli-occupied West Bank and Gaza Strip. But mentioning U.N. Resolution 242, Kaddoumi departed from the text of his speech to add the words "which we reject," bringing a burst of applause from the more than 250 delegates attending the meeting.

Resolution 242, adopted after the 1967 Middle East war, calls for Israel to withdraw from territories it captured in that conflict in return for peace with its Arab neighbors. The PLO has always objected to the resolution because it refers to Palestinian "refugees" and does not call for the creation of an independent Palestinian state, which remains the PLO's primary objective.

Kaddoumi's speech today did not constitute a formal reply to Hussein, and none is expected until the PLO elects a new executive committee at the conclusion of the meeting next week.

But his public rejection of Resolution 242 clearly reflected the prevailing attitude among PLO officials and delegates to the conference after Hussein's appeal. A final adoption of this position would seem to close the door on U.S. and Western European peace initiatives centered on Resolution 242.

"The PLO's stance toward U.N. Resolution 242 is clear and has not changed," Khalil Wazir, the deputy commander of PLO forces, told reporters before Kaddoumi made his report to the the PNC meeting.

[Israeli Foreign Minister Yitzhak Shamir, speaking on Israeli radio today, flatly rejected Hussein's appeal to Israel to seek peace on the basis of Resolution 242, calling it "the same old demand" made in the past, United Press International reported.]

Hussein made his appeal to the PLO Thursday night in a speech opening the meeting. He warned the PLO that time was rapidly running out on hopes of ever regaining the occupied territories and scolded the organization for wasting its energies on internal disputes.

Telling the Palestine National Council delegates that it was time for a "fresh approach," the king specifically called for the convening of a U.N.-sponsored international peace conference and the forging of a joint Jordanian-Palestinian negotiating position based on Resolution 242 as the basis for peace talks.

Kaddoumi said that Jordan's close ties to the West Bank Palestinians and Israel's settlement policies in the territory "require that we double our efforts to achieve a clear Jordanian-Palestinian policy in order to free our occupied land, and to block all the Zionist plans that are aimed at destroying the Palestinian national character."

However, by adding that the PLO continues to reject Resolution 242, Kaddoumi made clear that if such a policy does evolve from this meeting it will not be based on the "territory for peace" formula of the U.N. document.

The themes of Kaddoumi's report to the Palestine National Council were similar to those struck Thursday night by PLO Chairman Yasser Arafat in opening the meeting, which is being boycotted by Syrian-supported PLO dissident groups that have called for Arafat's ouster.

Recalling the attempts to amend the deep split that has developed in the PLO, Kaddoumi said, "Since the beginning, Syria's sympathy for the dissident movement never lessened. Despite this, the Central Committee of Fatah the mainline PLO organization headed by Arafat is prepared to have a wide-ranging dialogue with the Syrian leadership to reach a complete understanding about our joint relations."

One source of the continuing friction between the PLO and Syria is Arafat's decision to resume the organization's ties with Egypt despite the Egyptians' peace treaty with Israel. Making clear that the PLO will not back down from this course, Kaddoumi said, "We find ourselves seeking to find a unified Arab position to help Egypt break its chains and return to the Arab fold, with all its strength and power."

Much of Kaddoumi's report reiterated standard PLO positions. He accused the United States of continuing "imperialist policies" in the Middle East, and he called for stepping up the "armed struggle to regain the West Bank and Gaza Strip."

As the meeting continued, security remained extremely tight in the Jordanian capital. This morning security forces dismantled an 18-pound bomb that had been planted outside the American Center of Oriental Research.