President Anwar Sadat of Egypt, one of the strongest supporters of an early Geneva conference on the Middle East, apparently no longer believes that such peace talks are possible this year.

Sadat, aligning himself with the Syrian view that a Geneva conference now would be premature, last night renewed his call for a preliminary conference to work out the terms for Geneva.

Sadat's stance appeared to drastically reduce American hopes expressed publicly by President Carter and his senior aides that the Geneva conference would be reconvened before the end of the year.

But informed analysts here said Sadat's proposal may break a diplomatic stalemate that could have prevented the Geneva conference from ever taking place.

The Egyptian leader's proposal for a preparatory conference, which was rejected by Syria when he first advanced it last summer, resurfaced during a television interview last night.

Tonight, however, Sadat's foreign minister, Ismael Fahmi, appeared to hedge Egypt's position by saying that Sadat had mentioned the old proposal "but had no intention to revive it."

The Egyptians seem to have been engaging in subtle diplomatic maneuvering in recent days since the impasse over the issue of Palestine representation and the future of the Israeli-occupied Arab territories appeared to be jeopardizing the entire concept of Geneva.

Sadat, who in the opinion of many observers here needs to maintain at least the illusion of progress toward peace in order to preserve political stability in Egypt has now offered a format for dealing with those issues without risking failure at Geneva.

After consultations with King Khalid of Saudi Arabia, Sadat has again declared that "Geneva is not an end in itself." He called for a preliminary conference to ensure that Geneva, if it takes place, will deal with substantive issues, not procedural matters.

That fits in nicely with the view held all along by the Syrians that a Geneva conference was only worth holding if certain basic principles notably Israeli withdrawal from all territories occupied in the 1967 war were agreed to in advance. Syria wants no part of a ceremonial Geneva meeting that would leave fundamental issues unresolved.

Up to now, diplomatic analysts here believed Sadat would go to Geneva on almost any terms if only to be able to claim some success for his policy of endorsing American initiatives and offering Israel peace for territory.

But as prospects for Geneva began to fade after the chilly Arab response to the U.S. & Israel working paper on the terms of the negotiations, Sadat has sought another formula.

In an interview on Egyptian television last night, he said that the United States, the Soviet Union, Israel, Egypt, Jordan, Syria, Lebanon and "the Palestinians" should participate in the preparatory conference.

This proposal was believed to have been discussed at a meeting today between Foreign Minister Ismail Fahmy and Mikhali Sitenko. Soviet undersecretary for Middle East affairs, who came here after stops in Syria and Jordan.

Sadat recently visited Romania, the only country in Eastern Europe that still maintains diplomatic relations with Israel. Israeli Prime Minister Menahem Begin was there before Sadat. Observers here believe Sadat had Romania in mind when he told the editor of the newspaper Al Akhbar should assemble for proximity talks, or indirect contacts, in some neutral country.

This proposal which was rejected last summer by Syria, comes after weeks of intensive consultations among the major Arab countries in which Egypt has moved closer to the Syrian position on some sentitive issues. They apparently now have worked out a coordinated stance.

Sadat pledged recently that Egypt would never sign a separate peace agreement with the Israelis. This was clearly intended to allay Syrian fears that Egypt's economic woes would compel it to accept such a solution. Informed diplomats say they believe Sadat is sincere on this point.

In additions, Egypt is espousing the Syrian view that there can be no Geneva conference without the Palestine Liberation Organizations, which Sitenko said in Damascus also the Soviet position.

Cairo newspapers on Thursday printed a statement from Foreign Minister Family that if Israel persists in its refusal to deal with the PLO in any way, the Geneva conference "will not be held, neither this year nor any other year."

Sadat's working group proposal would leave room for maneuver on this point.

The Arab states have been working hard to coordinate their policies on these issues. King Hussein of Jordan flew to Saudi Arabia for consultations shortly after Sadat left and is due here Sunday.The king was in Syria earlier in the week.

Arab foreign ministers are scheduled to meet in Tunis next Saturday and set a date for an Arab summit conference.