Prince Saud Faisal, foreign minister of Saudi Arabia, called on the United States to assume an impartial position in the Middle East and not to cast the region "into the cauldron" of superpower rivalry.

Prince Saud, who met at the U.N. Friday with Secretary of State Alexander M. Haig Jr., made no mention of the Reagan administration's controversial plan to sell the Arab kingdom five Airborne Warning and Control System planes. The administration views the sale, which is imperiled by congressional opposition, as part of its effort to strengthen the Persian Gulf region against Soviet expansionism.

The Saudi public position has been that Israel and not the Soviet Union poses the biggest threat to peace in the Middle East. But, in addressing the 36th session of the U.N. General Assembly, Prince Saud castigated the United States and the Soviet Union equally for "endeavoring to create a military presence in the Indian Ocean and Arabian Sea."

Meanwhile, Iranian Foreign Minister Mir Hossein Mousavi Khameni, also addressing the Assembly, rejected claims that Iran bombed Kuwait last week, saying the charge by Iraq and the United States was intended to facilitate the sale of AWACS to "dependent clients" in the region.