President Anwar Sadat, brushing aside criticism by radical Arab states, declared today that he was determined to go ahead with the proposed Cairo meeting to prepare for a new Middle East peace conference, even if Israel and Egypt are the only countries attending.

"If no one is coming, okay, I shall deal with whoever comes," Sadat said in a televised interview on CBS's Face the Nation. "After that I shall be proceeding to Geneva."

As Sadat spoke, Arab leaders opposed to the Egyptian president's peace initiative were planning to meet in Libya on Thursday to plan their campaign against him.

Syria was the first country to formally reject Sadat's invitation to a preliminary conference that he plans to convene here next weekend.

The Syrian government statement came shortly after the Egyptian Foreign Ministry handed out invitations today to all parties in the Middle East conflict, including the United States and the Soviet Union as cochairmen of the Geneva conference.

In Jerusalem, Prime Minister Menahem Begin said Israel would accept Sadat's invitation regardless of the reaction of other Arab states. Israeli Foreign Minister Moshe Dayan, currently on an official visit to West Germany, was quoted as saying in Hamburg that Israel was ready to make compromises to achieve peace with its Arab neighbors.

Since the Palestine Liberation Organization had already announced that it would boycott the Cairo meeting, the PLO and the Syrians are expected to attend the meeting in Libya instead, probably joining Iraq and Algeria in a bloc of Arab states determined to resist Sadat's course of negotiating directly with Israel.

Other nations invited by Sadat - including the United States, the Soviet Union, Jordan and Lebanon - have yet to make official responses, but Sadat made it clear again today that if nobody comes but the Egyptians and the Israelis, the talks will begin.

He said he would go to Geneva to negotiate not just on behalf of Egypt but on behalf of all the Arabs who would be involved in a comprehensive settlement with Israel, and any peace agreement reached at Geneva would be submitted to an Arab summit conference where "each will have to make up his own mind."

Sadat said today that those nations that accept his invitation to Cairo could decide for themselves what level of official to send, but Egyptian sources said they were expecting ambassadors, not foreign ministers.

The Sadat invitation has put some of the invited countries in an uncomfortable position. The Soviet Union, which would be reluctant to sit out a conference that could have a vital role in determining the future of the entire Middle East, is cool to the Sadat initiative and closely linked to the Arab states that oppose it.

Moscow's response is not expected until after a visit there early this week by Syrian Foreign Minister Abdel Halim Khaddam, who announced the plans today for the anti-Sadat gathering to be held in Libya. Khaddam is to go to Moscow on Monday.

Also on the spot are Jordan and to a lesser extent Lebanon, which run the risk of missing talks that could determine the future of the Arab-Israeli relationship.

There is still uncertainty over whether there will be any Palestinians at the Cairo conference and if so whom they will represent. Egyptain officials say the PLO was invited, but PLO spokesmen in Beirut have said the PLO will not come.

Sadat strongly implied today that perhaps some other Palestinians will be authorized by the PLO to negotiate on their behalf.

"The PLO is so broad minded, they will solve the problem for us, in spite of what is happening now, all this shouting," Sadat said today.

He said that the Cairo conference, whoever attends it, would determine the procedures and format for Geneva, and the Geneva conference would seek a comprehensive settlement, and this process is now under way whether the Arabs like it not. "I am not after a separate settlement" between Egypt and Israel, he said once again.

He said the Egyptians the Israelis and whoever else takes part in the Cairo preliminary conference would all meet together "around one table." He said he would have more of the old system of having rival parties assemble in separate hotel suites with messengers shuttling between them.

Special correspondent Joseph Fitchett reported the following from Birut:

While seeking to confine Sadat's diplomatic initiative essentially to an Egyptian-Israeli consultation, Arab radicals are said here to be conscious that they were heightening the risk of Sadat's taking new steps in bilateral negotiations with Israel.

"This time, it is not just a visit; the Cairo meeting starts the negotiating process," said a source here in touch with top Syrian officials.

The Syrians apparently are trying to push the Soviets toward boycotting of the Cairo meeting. Soviet policy is slightly ambiguous, Syrian sources here point out. Moscow cetainly opposes Sadat bitterly, but probably would prefer a Geneva conference to a split in Arab ranks, which would eliminate any Soviet role.

The PLO has warned Palestinians in the occupied territories against coperating with the Sadat initiative. Public death threats against "collaborators" have been issued here by the Popular Democratic Front, a pro-Soviet guerrilla group.

With the PLO excluding itself, Sadat is expected to invite Palestinians from the West Bank and the Gaza Strip to Cairo.

More conservative figures, notably Gaza Mayor Rashid Shawa and like minded notables are known to be sympathetic to Jordanian thinking, which favors the emergence of a West Bank leadership that would resist a PLO takeover.