The message was conveyed before a speech on Saturday in which Iranian President Masoud Pezeshkian apologised to neighbouring Gulf states for Tehran's actions -- an apparent attempt to defuse regional anger over Iranian strikes that hit civilian targets.
Two days earlier, Saudi Foreign Minister Prince Faisal bin Farhan spoke to Iranian Foreign Minister Abbas Araqchi and set out Riyadh's position with clarity, the sources said.
Saudi Arabia is open to any form of mediation aimed at de-escalation and a negotiated settlement, the sources quoted the minister as saying, underlining that neither Riyadh nor other Gulf states had let the US use their airspace or territory to launch airstrikes on Iran.
But Prince Faisal was also quoted by the sources as saying that if Iranian attacks persisted against Saudi territory or energy infrastructure, Saudi Arabia would be forced to permit US forces to use their bases there for military operations. Riyadh would retaliate if attacks on the kingdom's critical energy facilities continued, he said.
The sources said the kingdom had remained in regular contact with Tehran through its ambassador since the US and Israeli military campaign against Iran began on February 28 following the collapse of talks on Iran's nuclear program.
The Saudi and Iranian foreign ministries did not respond to requests for comment.
The United Arab Emirates, Kuwait, Qatar, Bahrain and Saudi Arabia have all come under heavy drone and missile fire from Iran over the past week.
Iran's Supreme Leader, Ayatollah Ali Khamenei, was killed on the first day of the war. Tehran responded by hitting Israel and Gulf Arab states hosting US military installations, and Israel has attacked Lebanon's Iran-backed Hezbollah armed group.
Two Iranian sources confirmed that a call had taken place in which Riyadh warned Tehran to halt attacks on Saudi Arabia and neighbouring Gulf states.
Iran, they said, reiterated its position that the strikes were not aimed at Gulf countries themselves but at US interests and military bases hosted on their territory.
One Iranian source said that Tehran had in response demanded that US bases in the region be closed and some Gulf states stop sharing intelligence with Washington that Iran believes is being used to carry out attacks against it.
Another Iranian source said some military commanders were pressing to continue the strikes, accusing the US of using bases in Gulf states and these countries' airspace to conduct operations against Iran.
Iran had in recent years mended fences with its Gulf neighbours, including former regional arch-rival Saudi Arabia. The diplomatic campaign imploded in the blitz of drones and missiles launched by Iran's Revolutionary Guards in the past week.
