Iran said on Monday it was continuing talks with mediators from Qatar, Pakistan and Oman in an effort to prevent any further escalation in its war with the United States.
"The role of the mediators is to continue their efforts to prevent an escalation of tensions," said Iranian foreign ministry spokesman Esmaeil Baghaei Hamaneh.
Iran's Revolutionary Guards said they had targeted on Monday US military facilities in Bahrain and Kuwait, destroyed radar systems in Oman, and hit fuel tanks and ammunition depots at Prince Hassan Air Base in Jordan in response to US strikes.
The US military said it had struck on Sunday Iranian air defence systems, coastal radar sites, missile and drone capabilities and small boats, using aircraft, naval vessels and drones.
The exchanges were an escalation in the pace and geographic scope of attacks over the past week, casting doubt on an interim US-Iranian agreement signed last month to reopen the strait and end the war after a further 60 days of negotiations.
US President Donald Trump said he considers the ceasefire over, while leaving the door open to further talks.
Iran's top negotiator, Mohammad Baqer Qalibaf, struck a similarly defiant tone, posting on X on Sunday: "The era of one-sided deals is OVER. We told you: keep your word or pay the price. Reality is knocking."
The war launched by the United States and Israel against Iran on February 28 has destabilised the Gulf and spread across the region, with Iran attacking U.S. bases in multiple countries. Thousands of people have been killed, mainly in Iran and Lebanon.
Tehran's effective blockade of the Strait of Hormuz has driven energy prices higher and fuelled inflation concerns worldwide.
Brent crude rose more than three percent on Monday, although it remained well below peaks reached earlier in the conflict.
Higher energy prices, especially for gasoline, are politically sensitive for Trump ahead of November's congressional elections.
