Saudi Arabia's foreign minister, Prince Saud Faisal, and a delegation from other Arab states will come here during the first 10 days of September to confer with the Reagan administration about measures to end the Persian Gulf war between Iran and Iraq.

Clovis Maksoud, the Arab League representative here, said yesterday that the delegation wants to discuss ways in which the U.N. Security Council might prod Iran to accede to the cease-fire called for by the council on July 20.

In another Middle East development, the State Department formally announced yesterday that President Reagan has decided to send Ambassador William L. Eagleton Jr. back to Syria. Eagleton was recalled last Oct. 24 to protest Syrian complicity in an attempt to bomb an Israeli jetliner at London's Heathrow Airport. Department sources revealed last week that he would return to Damascus around Sept. 1 to reopen the channel for a U.S. dialogue with President Hafez Assad's government.

In addition to trying to put its relations with Syria on a new footing, the administration, despite its professions of neutrality, has tilted strongly toward the Arab states supporting Iraq in the gulf war. The United States currently has more than 30 warships in the gulf area helping to protect tankers belonging to Iraq's ally Kuwait that have been "reflagged" under American registration; and, on the diplomatic front, the administration has taken the lead in seeking to put pressure on Iran through the U.N.

U.S. diplomats have started to explore with other Security Council members the possibility of following up the July 20 resolution with another calling for an international arms embargo against Iran. Iraq has expressed willingness to accept a cease-fire, but on Wednesday, Iranian Prime Minister Mir Hossein Mousavi rejected what he called an American and Arab attempt to impose "an ignominious peace" on his country.

Maksoud said that Arab League delegations will visit the other four permanent members of the Security Council: Britain, France, the Soviet Union and China. However, while the United States has made clear its willingness to support a sanctions resolution, China, which supplies weapons to Iran, and the Soviet Union, which has been improving its ties to Tehran, have shown no enthusiasm for sanctions.

Reports from Tehran yesterday quoted Iranian President Ali Khamenei as saying that the United States and the Soviet Union had plotted to crush Iran between "two blades of the West-East scissors." But, he added, Moscow had "come to its senses" and had backed out of the plot.

Since Syria and Iraq are bitter enemies, the return of Eagleton to Damascus seemed to be aimed less at influencing the gulf war than at cultivating Syrian cooperation in the fight against international terrorism and in creating the conditions for Arab-Israeli peace talks.

State Department spokeswoman Phyllis Oakley called the U.S. action "a measured response to positive steps the Syrian government has taken" in clamping down on terrorist organizations that operated from Damascus. She added: "Syria is a major Middle Eastern state with which the United States maintains a dialogue, notwithstanding differences between us."

The United States last week thanked Assad for Syria's efforts on behalf of Charles Glass, an American journalist who had been held hostage in Lebanon. However, Oakley said the decision to send Eagleton back had been made before Glass surfaced in Beirut, saying he had escaped from his captors.

Oakley said economic sanctions imposed by the United States against Syria last November would remain in place, as well as a ban on high-level contacts with Syria by U.S. officials other than Eagleton.