Saudia Arabia will help bring other Arab nations and the Palestinians into a final and full peace settlement with Israel in return for a formal Israeli promise to withdraw from the Arab lands occupied in 1967, Crown Prince Fahd has declared.

"There will be men and countries in the Arab world who will take the Israeli word seriously," Fahd said in an interview. "If Israel would declare its sincere intention of withdrawing the lands occupied in 1967, Saudi Arabia would do its utmost to bring the Arabs to cooperate and work for a full settlement."

All Israeli governments since 1967 have refused to commit themselves to a complete withdrawal from occupied Arab territories, including East Jerusalem, and the present Cabinet headed by Prime Minister Menachem Begin has been particularly adamant about not pulling out from the West Bank. Fahd's proposal appeared likely to elicit only a negative response from Begin.

But Fahd's suggestion, which came during an interview with the chairman of the Washington Post Co., Katharine Graham, in the royal palace, did seem to mark a significant step forward in Saudi Arabia's own position on reaching a final Middle East peace settlement. Previously the Saudis, who have sharply attacked the Camp David peace process, have demanded that firm deadlines be established for Israeli withdrawal from the West Bank and Jerusalem before they would actively support full peace talks.

"There can be a program for withdrawal to be discussed, to be negotiated in detail with the other parties," Fahd said. "U.N. Resolution 242 was accepted by Egypt, Israel, Jordan and Syria. This can be made a basis for a peace settlement."

Saudia Arabia for many years refused to acknowledge the Security Council resolution to which Fahd referred as a basis for a peace agreewment. The resolution calls for security guarantees for Israel in return for withdrawal from unspecified amounts of the territories occupied in 1967. It treats the Palestinians only as a refugee problem.

The appearance of new Saudi movement on peace, which came as Monday's Camp David target date on West Bank autonomy approaches, was buttessed by a pledge in a separate interview from prince abdullah ibn Abdul Aziz, the second deputy prime minister and commander of the kingdom's National Guard. Abdullah suggested that Arab states would guarantee peaceful Arab-Israeli coexistence if a Palestinian state is created.

The theory that a free Palestinian state on the West Bank will be communist or a base of instability is completely wrong," said Abdullah, who has been one of the royal family's most vigorous critics of Israel and of Zionism in the past. "If the Palestinians get an entity of their own, then the other Arab states will help them develop their country and make it stable."

Asserting that Arabs had realized over the past five or six years that war with Israel "hurts everyone," Abdulah continued "We and the Jews are cousins. We are all semites. Now in every Arab country the climate is ready for peace."

Saudi Arabia is the world's largest oil exporter and one of the main bank-rollers of the Palestine Liberation Organization. The Saudis also provide financial assistance to Syria, which lost the Golan Height to Israel in the 1967 war, and to Jordan, which lost the West Bank.

But the Saudis have been reluctant to use the leverage this financial help provides, and have been evasive when pressed for their own ideas about final peace settlement.

The statements by Fahd and Abdullah, who effectively run the country under the reign of their infirm elder brother, King Khalid, indicate that the deadlock in the autonomy talks has produced a Saudi reassessment.

Responding in Arabic through an interpreter, Fahd spoke forcefully during the 90-minute interview, although his voice was slightly hoarse.

Troubled by overweight and heart problems periodically in recent years, Fahd appeared last week to be vigorously pursuing his role as chief executive oficer of the kingdom.

Both Fahd and Abdullah sharply attacked unspecified U.S. press reports about dissention within the royal family, and complained of a mounting campaign abroad to distort Saudi Arabia's image. Abdullah also promised a crackdown on Arab middlemen who have collected enormous commissions for placing contracts in Saudi Arabia and thereby "presenting a distorted image of the kingdom to the rest of the world." t

Other points in the interviews included:

Fahd and Abdullah suggested obliquely that they had reason to hope that the American hostages in Iran would be released soon, but they declined to provide details. Saudi Arabia played a key role in the Islamic foreign ministers' conference last week that considered the hostage situation.

They urged the United States to provide large amounts of military aid to Pakistan and Somalia immediately. "Pakistan did not really refuse the help of America. It was only that the help was too small," Fahd said. "If Pakistan had accepted this help, it would have given the Soviet Union or Afghanistan the pretext to attack Pakistan and Pakistan would not have had the resources to defend itself. Pakistan would in fact welcome help and friendship with the United States."

Fahd said that Saudi Arabia does not favor joint security efforts with the United states in the Persian Gulf area. "I don't see anything threatening our security in the Gulf. Moreover, if you take any action that is not needed, this action may create more trouble than you are trying to control."

The crown prince also suggested that Saudi Arabia would support the holding of a limited conference of world leaders that would seek to reach a global economic agreement, including an energy compact. "Anything that would bring down the prices of manufactured goods sold by developed countries to oil producers would act to bring oil prices down," he said.