The United States, in a bid to win Soviet backing, has agreed to delay temporarily the implementation of an international arms embargo against Iran to permit U.N. Secretary General Javier Perez de Cuellar to make another effort to end the war in the Persian Gulf through negotiations.

State Department officials said the new U.S. proposal was submitted to Soviet leader Mikhail Gorbachev and Foreign Minister Eduard Shevardnadze in Moscow earlier this week by Secretary of State George P. Shultz. The Soviet leaders said they would consider the plan, sources said, and their attitude left Shultz and some of his aides encouraged that Moscow might finally accept the long-discussed arms embargo.

The two nuclear superpowers worked together last July in promoting the unanimous passage of U.N. Security Council Resolution 598 demanding that Iran and Iraq stop fighting and return to internationally recognized boundaries. Since then, Washington has been trying to persuade Moscow to support a follow-up resolution imposing a sweeping arms embargo against Iran for failing to accept the U.N. demand, which Iraq said it would accept.

The Soviet Union has balked at approving the arms embargo against Iran, arguing that diplomacy should first be exhausted. U.S. officials say Moscow is reluctant to endanger its relations with Iran by approving an arms embargo, especially at a time when Iran is in a position to affect the course of a Soviet pullout and future developments in neighboring Afghanistan. On the other hand, the Soviets are under pressure from Arab nations to agree to the arms embargo.

The Soviet Union agreed last week to approve circulation of the text of a proposed arms embargo resolution among the 15 Security Council members, but has declined to approve or disapprove the substance of the measure. The plan, offered by Britain with strong U.S. backing, calls for a halt in the sale of arms, spare parts, arms manufacturing facilities and military training services to Iran.

The new U.S. suggestion is that the United Nations quickly vote an arms embargo, but that implementation be delayed about 30 days to allow one last appeal by Perez de Cuellar to Iran to accept the cease-fire and return to state boundaries before the embargo is imposed.

The U.N. secretary general visited Tehran last September in an unsuccessful appeal to Iran to stop fighting.

The Soviet news agency Tass said Tuesday that Gorbachev, in his Kremlin meeting that day, promised Shultz "to discuss some ideas" about the Persian Gulf, evidently a reference to the change in the U.N. resolution that Shultz had brought.

Shevardnadze told reporters then that "there is very detailed, active and intensive work under way" in the Security Council to outline further U.N. action. He emphasized, as Shultz had done in a news conference en route to Moscow, the need for "collective efforts, collective work" on the part of all Security Council members.

The United States hopes to move for a vote on the arms sanctions by next Monday, the last day when U.S. Ambassador Vernon Walters holds the rotating presidency of the Security Council. Diplomatic sources said, however, that chances are dim that the Soviet Union and several others in the 15-nation Security Council will be ready for a vote that quickly.