President Anwar Sadat met with U.S. special envoy Alfred Atherton yesterday as plans were announced in Jerusalem for a meeting in Washington next month between President Carter and Israeli Prime Minister Menachem Begin.

The two moves, aimed at bringing about a resumption of the Middle East peace negotiations, came as speculation mounted that the United States is preparing to submit its own proposals to break the deadlock.

A spokesman for Begin said the Israeli leader will meet Carter in early May while he is in the United States for a tour marking the 30th anniversary of Israel's independence.

Begin is to arrive in the United States May 1 but no date has been announced for his meeting with Carter.

Carter and Begin met in Washington Post last month and their talks ended with the two sides in disagreement about Israeli peace proposals, especially the amount of occupied territory that Israel should return to the Arabs.

Artherton conferred with Sadat for 2 1/2 hours at the Red Sea port of Hurghada. In characteristically cautious comments to reporters afterward, he said he was "confident that ways can be found to being again to move the peace process forward."

He appeared to be clarifying and defining the specific terms on which Egypt would agree to resume direct talks with Israel, in preparation for an American attempt to induce the Israelis to accept those conditions.

The American diplomat was the U.S. delegate to the abortive Cairo peace conference in January and later shutteled from here to Jerusalem in a vaineffort to find language for a Proposed declartion of principles that Egypt and Israel could both accept. "We are not at the stage where we or anyone else are putting forward proposals," he said yesterday.

But those who beliveve that the only way out of the current impasse is for the United States to offer its own language and force the Israelis to accept it found new clues to support their view in Atherton's remarks. The clues appeared as well in a major review of the negotiating situation that he gave in a speech in Atlanta early this month.

Atherton said Sadat reiterated that direct Egyptian-Israeli negotiations could only resume if Israel indicated it was ready to soften it positions on the key issues: Palestinian rights and withdrawal from occupied Arbab territory. As Egyptian Foreign Minister Mohammed Kamel said, "It is only natural that there must be a change in Israeli positions before we resume talks, and this has not happened til now."

Atherton noted that "there are issues where we and Israel have our differences and we feel these have to be talked out and ways have to be found around them."

Given that observation and his statement of confidence that a way could be found to get the talks restarted, Egyptian observers found indications that the Americans are preparing to take action. They noted that Atherton did not mention any differences between U.S. and Egyptian positions.

In fact, the reason the Egyptians would be happy to see the Americans submit their own proposed language is their belief that on every major issue in the Middle East at this time - Palestinian rights, Israeli withdrawal from occupied territory, arms sales - Washington's views are much closer to those of Cairo than they are to those of Jerusalem.

The Egyptians believe they have a U.S. commitment to offer wording, probably incorporating alrady accepted by Sadat in his meetings with President Carter, if it becomes necessary to break the deadlock.

Atherton said, as he and secretary of State Cyrus Vance have before, that the United States would take such a step if "we feel this will help make a contribution for the advancing of the negotiations."

Atherton also said Sadat offered to send Foreign Minister Kamel to the United States for discussions if it would be useful but no decision had been made. He said Sadat had given him a personal message to deliver to President Carter