The Soviet Union is ready to establish "working contacts" with the United States to prepare for an international conference on the Middle East but will not drastically revise its regional policies, as called for by Washington, to open the way for such a conference, a leading Soviet expert has said.

In the first authoritative public Soviet reaction to U.S. assertions last week that hopes for progress in the Middle East were being blocked by Soviet refusal to reestablish diplomatic relations with Israel and other Soviet stands, Evgeni Primakov predicted that the Soviet Union would not accept "one side setting preconditions for the other to meet."

Primakov, whose position as director of the government's Institute of Oriental Studies makes him an authoritative voice on Soviet views of the Middle East, also voiced criticism of the agreement reached between Jordan's King Hussein and Palestinian leader Yasser Arafat for a joint approach to Middle East peace efforts.

"Not everything Arafat has done in recent months has benefited the Palestinians," Primakov said in an interview here yesterday. His unusually candid criticism of the Palestine Liberation Organization chairman focused on the Feb. 11 agreement with Hussein and "the enmity toward Syria" that he said Arafat had shown.

Throughout the interview, Primakov laid heavy emphasis on Moscow's willingness to reach accommodation with Washington on Arab-Israeli negotiations and on the Persian Gulf as long as Soviet interests were taken into account. And in contrast to his acerbic criticisms of Arafat, he offered conciliatory assessments of Soviet relations with conservative Arab governments such as Saudi Arabia and Egypt.

Diplomatic sources noted that the Soviets in recent months have sought to improve relations with prowestern Arab governments and with Israel, perhaps in hopes of playing a larger role in peace negotiations if King Hussein is successful in his renewed efforts to involve the United States, the Palestinians and Israel in a political dialogue.

But his curt rejection of U.S. calls for Soviet policy changes and his criticism of the Arafat-Hussein agreement appeared to undercut hopes by Hussein that the Soviets would acquiesce in playing a nominal role in an international conference.

American officials said the U.S. Embassy here had not formally relayed to the Soviet government the State Department list of steps that the Soviets could take to establish a better international context for negotiations, and Primakov said that he was not aware of the specifics of the proposal.

On May 30 a State Department official listed several actions that the Soviets could take that the United States would consider "constructive behavior." Among them were resuming full diplomatic relations with Israel, improving the treatment of Soviet Jews, ending arms aid to militias in Lebanon and ending anti-Semitic propaganda.

Primakov's reaction left no doubt that the Soviets would find the U.S. offer unacceptable.

The Soviets already had indicated their unease with the agreement reached by the Jordanian monarch and the Palestinian leader. The agreement is intended to lead to the formation of a joint Jordanian-Palestinian delegation to negotiate with Israel on the return to Arab sovereignty of the occupied territories of the West Bank and Gaza Strip.

Primakov voiced concern that the agreement "could open the door to a separate deal" with Israel that would not lead to the formation of a national Palestinian state. The agreement speaks instead of a confederation of the Palestinians with Jordan.

Syria, a Soviet ally and supporter of Palestinian rebels who are challenging Arafat's authority over the guerrilla movement, also has condemned the Feb. 11 agreement sharply.

Primakov emphasized that the Soviet Union would participate in an international conference that would seek "a comprehensive settlement in the Middle East" and was ready to establish "working contacts with the United States to prepare" for such a conference.

"It is not true that we propose that all of the problems have to be resolved in a package deal simultaneously -- like that," he said, snapping his fingers. "We believe there can be interim solutions along the way as long as they are not separate deals. The conference could go on for a considerable time and certain specific questions be dealt with specifically but within the framework of a general solution."

His remarks appeared to bolster Jordanian reports that Soviet Foreign Minister Andrei Gromyko had informed Jordan privately that Moscow wanted to cosponsor an international conference with the United States rather than simply participate as a member of the U.N. Security Council.

Asked about several specific points of the U.S. conditions, Primakov said that it was premature to ask the Soviet Union to recognize Israel as a condition for holding a conference.

"In my opinion, the work of the conference would give some possibility to advance in this direction, but there is much precedence, even on the American side, of working with countries in the Middle East in such a situation without having diplomatic relations." He specifically mentioned U.S. contacts with Egypt, Syria and Iraq before diplomatic relations were reestablished.

He also cited the resumption of U.S.-Iraqi relations this spring as an example of the possibility of Washington and Moscow finding accommodation in the region. "The Americans know very well that we did nothing to interfere with that," he said. He also asserted that the Soviets have been trying to improve relations with Egypt but that they do not expect it to be at the cost of U.S.-Egyptian relations.

On other topics, Primakov said:

* The Soviet Union is ready to reestablish full diplomatic relations with Saudi Arabia as soon as the kingdom makes the decision to do so. "We are open for developing good relations with Saudi Arabia," whose foreign minister, Prince Saud Faisal, visited Moscow earlier this year.

* The Soviet Union recognizes that guaranteeing the free flow of oil from the Persian Gulf is a matter of international concern and is prepared to discuss this in detail with the United States.

* Soviet troops will withdraw from Afghanistan when that country's "neutrality and independence" can be guaranteed without Soviet troops. "We do not want to make Afghanistan an artificially socialist country. We know that we could not do that."