American Jewish leaders, after unprecedented meetings with Jordanian and Egyptian officials, said today that those Arab officials strongly urged that the Palestine Liberation Organization "be put to the test" by the United States on the issue of publicly recognizing Israel's right to exist.

Officials in Amman and Cairo also "broadly hinted" that they might be prepared to drop the PLO from negotiations if its chairman, Yasser Arafat, refused to make such a declaration after a proposed joint Jordanian-Palestinian meeting with U.S. Assistant Secretary of State Richard Murphy, according to one of the Jewish leaders.

The 20-member delegation from the American Jewish Congress met with Jordanian King Hussein and Egyptian President Hosni Mubarak and other officials of the two countries in what they described as a "fact-finding mission." It was the first time such a delegation had met with Hussein or Mubarak.

Members of the delegation said at a press conference here that leaders of both countries stressed that Arafat and other "certain elements" of the PLO had moderated their positions and were prepared to live at peace with Israel if a Palestinian homeland, federated with Jordan, were to become a "realistic possibility."

Theodore Mann, president of the American Jewish Congress, said the Egyptian and Jordanian officials told the delegation that the tendency toward PLO moderation would be enhanced if the U.S. government opened a dialogue with Arafat.

"What they kept telling us was, 'Let us move toward the Murphy meeting,' because the Murphy meeting contains the clear stipulation or promise that after it is held, the PLO is supposed to make a statement that recognizes Israel's right to exist," said Henry Rosovsky, cochairman of the congress' board of trustees.

Rosovsky added, "Then I think we got a sense that if the PLO did not make those statements, they the Egyptian and Jordanian officials might then be prepared to drop the PLO. That, I would say, was broadly hinted to us."

Neither Rosovsky nor the other members of the panel specifically linked either Mubarak or Hussein to the suggestion of dropping the PLO from the joint Jordanian-Palestinian delegation.

But Rosovsky said that in Washington and the Arab countries the panel visited, "there was a low probability assigned to the PLO making those statements if the Murphy meeting was held."

One of the delegates, who met with Hussein Monday and reported their conversation today to Israeli Prime Minister Shimon Peres, said they are "convinced that this is indeed a moment of crucial importance for progress toward enlarging the peace and for the beginning of a solution of the Palestinian problem."

After being briefed by the American group, Peres said in an interview with The Washington Post, "I was aware of this, the actual positions of the Egyptians and the Jordanians. I think the PLO introduced a real setback to the whole process."

A delegation member reported at the press conference that Egyptian and Jordanian officials said the international peace conference demanded by Hussein and Arafat was only a "formality to enable negotiations to get off the ground."