Egyptian President Anwar Sadat today invited all parties in the Middle East conflict, including Israel, to Cairo next Sunday to begin making preparation for a new peace conference.

He said he wanted the Arab states, the Soviet Union, the United States and Israel to meet here "so we can sit and make preparations for the Geneva conference and discuss the case in a matter of months, not years."

Israel quickly expressed its willingness to come and said it would make an official response when it received the formal invitation. Sadat's invitaion is the first that any major Arab head of state has ever extended to Israel.

Other reactions, however, were less enthsiastic.

Syria , which boycott the original Geneva peace talks in 1973, rejected Sadat's invatation outright.The Soviet Union made no official response but Tass, its official news agency, criticized Sadat's offer.

A spokesman for President Carter said the United States "will be consulting with those invited to determine their willingness to meet in Cairo to prepare for the Geneva conference."

A State Department spokesman said that the United States beleives Sadat's proposal "could be painful"

Officials in Washington said that the United States had been informed in advance of Sadat's plan to issue the invitation. U.S. diplomats at the various capitals involved will take soundings and report to Washington before the United State responds to Sadat's invitation, it was learned.

Sadat's proposal clearly grew out of his historic and dramatic visit to Israel last Weekend, a trip that established for the first time a forum for direct, public contact between Israel and an Arab contfrontation state.

In an 80-minute speech to Egypt's Parliament, Sadat stressed to his commitment to peace and the sense of urgency that complelled him to take the drastic step of going to Israel. But he left many questions unanswered about his proposal to bring the parties to Cairo confront the procedural questions.

He didi say which Palestinians would be invited. However, acting Foreign Minister Butros Ghali said that the Palestine Liberation Organization will be invited, despite its hostility to Sadat's Israel visit.

In Beirut, guerrilla leader Yasser Arafat convened an emergency session of the PLKO executive committee study the Sadat offer.

Sadat did not say if Lebanon would included in the invitation, or what [WORD ILLEIGBLE] of officials will be asked to [WORD ILLEGIBLE] Most important, he did not say what would happens if his latest surprise initiative fails to get real peace talks started.

Sadat believes that a Geneva conference called now could fail because of hanging over what he calls "procedures" notably the refusal of Israel to have any dealings with the PLO or its representatives.

He indicated that during his visit to Israel he formed reason to believe that procedural matters could be trashed out quickly in a preliminary conference, thereby avoiding an impasse at Geneva.

"Nobody expected us to reached a comprehensive overall solution in two days," he said of his talks in Jerusalem.

But he said it was agreed that all paaticipants in the conference would "tackle in the matter with courage" and not hide behind procedural issues. When negotiator deal with the concept of security, vital to the Israelis, "this should be away from any conception of annexation: or expansion," sadat said.

This suggested that Sadat has made heavyway in convincing Israel of two points: that its national security lies in a negotiated peace, not in armed occupation of the territories captures in the 1967 war, and that there is room for mancurver, on the Arab side, the Israel side or both, on the question of Palestinian representation.

He strongly implied that even if his initiative today fails, he is going to go ahead with his peace campaign, taking it upon himself to negotiate for all the Arabs of Syria and the PLO refuse to cooperate.

Syria has already said it will not participate in any Geneva conference that meets as a result of the Sadat's intiative. The Syrian information minister, Ahmad Iskander Ahmed, said has only increased the enemy's intransignece and reinforces its refusal to withdrawl fron the occupied Arab territories and recognize the national rights of th Palestinian people.

The Soviet Union and several Palestinian groups have leveled similar criticism at Sadat. But today he fired right back, saying that far from abandoning these minimal conditions set by the Arabs for peace with Israel, he had gone to Israel to make it clear that there can only be peace if these terms are meet.

According to an unofficial translation, Sadat warned the Soviet Union that "if it puts any impediments in the way" of the Cairo talks orfo Geneva, "it will be making the biggest mistake to its life."

Saying he was "proud that i visited Jerusalem," Sadat described what he said were the fruits of his historic journey: "No responsible Israel today can doubt the genuine desire Arabs to reach peace." He said world opinion is not unanimous that it is up to the Israelis to take some bolds steps of their own.

He said Israelis themselves were made to understand that the Arabs will never give them peace as long as they continue to occupy Arabs lands and to refuse to accept a Palestinian state.

Sadat said that as na result of his visit "we accept a certain situation that we rejected in the past" - namely the right of Israel to exist in peace in the pre-1967 borders - but "no legal or hisstoric right of the Arabs was jeopardized in anyway." That included, he said, the Arabs claim to Easr Jerusalem.

He said that in the nearly 30 years of Arab-Isralei conflict, barries of doubts, suspicion and misunderstanding had been put up that trip had begun put up that his trip had begun to pull down.

As an example of how these doubts and susapicions made it urgent that his peace initiative go forward. he said. Egypt and Israel nearly blundered into an accidential war 10 days ago because of their suspicions of each other and the lack of communications.

The Israelis feared that Egypt was about to launch an attack, he said, and began maneuvers in the Sinai, leading Egypt to start maneuvers and move troops of its own. "They were very jittery," Sadat said.

The president said that while in Israel he discussed this with Gen. Mordechai Gur, the Israeli chief of staff, who had publicly warned that Sadat's trip was only camouflage for an planned surprise attack.