The Soviet Union has told Jordan that it is interested in attending a new Middle East peace conference but wants it to be cosponsored by Moscow and Washington rather than held under the auspices of the U.N. Security Council.

The message was conveyed to the Jordanian foreign minister, Taher Masri, during a visit to Moscow 12 days ago. It appears to have added a new complication to Jordanian efforts to convene a U.N.-sponsored international conference under which a joint Jordanian-Palestinian delegation would hold direct talks with Israel.

Masri said he was told by Soviet Foreign Minister Andrei Gromyko that Moscow opposed the participation of all five permanent members of the Security Council because it felt that Soviet influence would be diluted.

The Soviets "want to be just with the United States," Masri added.

Gromyko's reported comments to Masri were the first indications that Moscow has begun to take seriously the possibility of a new Middle East conference and to set forth its own ideas for how it should proceed.

Jordan is proposing that the U.N. Security Council convene the conference so that all five permanent members -- the United States, the Soviet Union, China, France and Britain -- would be present and provide international legitimacy for direct talks.

Both the United States and Israel have indicated strong opposition to the Jordanian plan because they oppose Soviet participation in any new Middle East peace talks. Israeli leaders have noted -- among other reasons for their opposition to a Soviet role -- that Moscow does not have diplomatic relations with Tel Aviv.

Whether Moscow, hoping to play a part in any new Mideast negotiations, might be reconsidering its position toward Israel remains unclear. Soviet Ambassador Anatoliy Dobrynin recently held another secret meeting with the Israeli ambassador here, Meir Rosenne. Israeli diplomatic sources said, however, that he gave no indication of any change in Soviet policy.

The meeting was held May 22 at Israel's request. It was the latest in a series over the past several years in which Israel explored subtle shifts in Soviet attitudes toward it. The Soviet Union broke off relations with Israel at the time of the 1967 Arab-Israeli war and said it would not renew them until Israel gave back all occupied Arab lands.

In 1977, however, when Moscow and Washington were discussing the reconvening of the 1973 Geneva Mideast conference, the Soviets let it be known that they were ready to resume relations with Israel in return for a role in the negotiations. But Egyptian President Anwar Sadat's trip to Jerusalem in November 1977 aborted the conference and ties were not restored.

Some analysts here think the Soviets might make the same offer again to gain a foothold in the Middle East peace process.

The Jordanian peace plan as described by Masri, however, would have Moscow playing only an initial role. It would be a convening power of an international conference whose main purpose would be to legitimize direct negotiations between Israel and a Jordanian-Palestinian delegation.

Masri noted that the Geneva conference that convened two months after the Arab-Israeli war of October 1973 held just one brief session, with the United States and the Soviet Union serving as co-chairmen. It immediately recessed to allow the United States to mediate a series of bilateral agreements between Israel and the Arab parties to the conflict.

"This is a good example of what could happen this time," he said. "Even if at a certain time the Soviet Union and Syrians don't attend, we can continue and we can conclude [an agreement]."