A senior Israeli official said today that U.S. involvement in secret diplomatic contacts with Jordan, Egypt and Israel over a possible comprehensive Middle East peace agreement is intensifying daily.

The official, who asked not to be identified, also said that other nations, such as France, may be used in behind-the-scenes efforts to reach a breakthrough for direct Israeli-Jordanian talks initiated in an international forum.

The main obstacles that are the focus of U.S. attention, the official indicated, are finding a suitable international forum that would lead to direct talks and the nature of Palestinian participation in talks with Jordan and Israel. Israel has rejected participation by the Palestine Liberation Organization.

The official also said that while Israel does not expect the Syrians to join the peace talks, it would be willing to negotiate with them and that the recent talks between Jordan and Syria to ease tensions between those two nations hold out some possibilities.

In conjunction with the reported increase in the "discreet" American involvement, Israeli officials also said that Prime Minister Shimon Peres has decided to rely exclusively on a strategy of "quiet diplomacy" in seeking direct peace negotiations with Jordan in the face of increasingly harsh criticism from some members of the right-wing Likud faction of his coalition government.

Peres was described by the sources as being in a "fighting spirit" and determined to seize the moment to initiate talks with Jordan even if it brings his "national unity" government close to dissolution.

Officials close to the Israeli leader said today that they were encouraged by the fact that in King Hussein's speech to the Jordanian parliament yesterday, the king did not call specifically for PLO participation as a condition for convening an international peace forum.

Peres has only 11 months left before he will have to turn the premiership over to Foreign Minister Yitzhak Shamir, leader of the Likud bloc, and he is known to be anxious at least to begin talks toward a peace pact with Jordan before then.

For their part, members of the Likud faction are showing signs of increasing frustration and worry that Peres may have enough time to reach a breakthrough with Jordan in opening peace negotiations, possibly gaining enough political capital to force an early election and seek a more favorable coalition.

Peres was said to be sanguine about recent press leaks here that he believes were designed to scuttle his peace initiative. The leaks, which a Peres aide termed "blatant disinformation," alleged that Peres made secret offers to Hussein containing sweeping concessions not approved by the Likud ministers of his Cabinet, which would constitute a violation of the coalition agreement. [Hussein, interviewed Sunday on NBC's "Meet the Press," said there was "no truth whatsoever" to these reports of secret offers and secret meetings.]

A senior Israeli official said Peres is convinced that an opportunity for peace with Jordan is so close at hand that it cannot be sabotaged by such political infighting. He described the prime minister as "charged up" by the challenge of bringing Hussein to the negotiating table.

Asked how quiet diplomacy could succeed in the face of almost certain further attempts at political undermining by some suspicious Likud ministers, the senior Israeli official replied, "It's not easy, but it's going better than you think."

A party with four seats in parliament, Tehiya (Renaissance), with backing by Trade Minister Ariel Sharon, caused a brief uproar last week by claiming to have seen a document in which Peres offered Hussein an interim peace agreement. The purported plan called for a form of limited Palestinian autonomy in the occupied West Bank, administered jointly by Israel and Jordan under a "condominium" arrangement.

The momentary crisis over the alleged secret document deflated almost immediately, and Likud leader Shamir joined Peres in issuing an unequivocal denial that an offer had been made.

Peres' deft management of that controversy, coupled with his decisive crushing of a Likud challenge to his peace initiative in parliament three days earlier, underscored what some political observers here have described as an increasingly sophisticated quest for opening a peace dialogue with Jordan.

Convinced that the Achille Lauro hijacking has effectively eliminated the PLO and its chairman, Yasser Arafat, from the peace process, Peres now has turned to the trade-off that his advisers regard as essential for Hussein if direct peace talks are to get under way. That is some sort of international auspices or framework to initiate negotiations while protecting Hussein from charges of seeking a separate peace treaty with Israel.

By couching such a format in euphemisms such as "international accompaniment," Peres has softened criticism by some Likud ministers that he is betraying the coalition agreement by taking peace talks to an international conference.

However, senior Israeli officials said they expect further Likud challenges to Peres' peace moves because of the power struggle that Sharon and Deputy Prime Minister David Levy are waging against Shamir in anticipation of next month's national convention of Likud's dominant Herut wing.

Both Sharon and Levy have appeared intent on keeping a crisis atmosphere alive and thereby forcing Shamir into the uncomfortable position of siding with Peres on a volatile issue, in the view of the political observers. Shamir appears equally intent on keeping the coalition intact until his rotation into the premiership next September.