The US and Iran appeared no closer to finding an end to their war after the two sides traded fire in the Gulf amid a tenuous ceasefire, while a US intelligence analysis concluded Iran could withstand a naval blockade for months.
Iranian officials accused the United States of violating the ceasefire with the tanker strikes and hampering diplomatic efforts to end the conflict.
A parallel ceasefire in Lebanon was also under strain.
Hezbollah launched missiles and drones at military bases in Israel in retaliation for a recent attack on Beirut and ongoing strikes in the south, where Lebanese authorities reported 11 people killed in Israeli attacks yesterday.
US Central Command said an F/A-18 Super Hornet used precision munitions yesterday against two ships in the Gulf of Oman, the gateway to the vital Strait of Hormuz, to prevent them from continuing to Iran.
An Iranian military official told local media the country's navy had "responded to the violation of the ceasefire and to American terrorism with strikes" and "the clashes have now ceased".
The latest incident came after another flare-up overnight in the strait, control of which an adviser to Iran's supreme leader compared to having "an atomic bomb".
Clashes extended beyond the waterway.
The UAE said its air defences engaged with two ballistic missiles and three drones from Iran yesterday, with three people sustaining moderate injuries.
US Secretary of State Marco Rubio reiterated that it was "unacceptable" for Iran to control the crucial oil conduit.
Speaking to reporters in Rome, Mr Rubio said Washington was expecting Iran's response to its latest proposal later in the day and expressed hope it would be "a serious offer".
Mr Trump, at the White House, later added: "I'm getting a letter supposedly tonight, so we'll see how that goes."
The US has sent Iran, via Pakistani mediators, a proposal to extend the truce in the Gulf to allow for talks on a final settlement of the conflict launched 10 weeks ago with US-Israeli strikes on Iran.
Iran's foreign ministry spokesman Esmaeil Baqaei said that the proposal was still "under review," according to the ISNA news agency.
Meanwhile, a US intelligence assessment has indicated that Iran would not suffer severe economic pressure from a US blockade of Iranian ports for about another four months, according to a US official familiar with the matter, suggesting that US leverage over Iran remains limited as the two sides seek to end a conflict that has been unpopular with US voters.
The Washington Post first reported the assessment.
A senior intelligence official called the "claims" about the CIA analysis "false," saying the blockade "is inflicting real, compounding damage - severing trade, crushing revenue, and accelerating systemic economic collapse".
Oil slick spreading near Iran's Kharg Island
Iran's UN envoy, Amir Saeed Irvani, accused the United States of violating the ceasefire with the attacks on the Iranian tankers, in a letter to the UN secretary-general and Security Council.
Qatar's prime minister, Sheikh Mohammed bin Abdulrahman Al Thani, met with US Vice President JD Vance in Washington yesterday and discussed the Pakistani-led efforts to broker a permanent peace.
Iran has repeatedly launched strikes on sites in Qatar during the war, pointing to the wealthy emirate's role as host of a major US air base.
Satellite images have meanwhile shown that an oil slick is spreading off the coast of Iran's Kharg Island, a key oil export terminal for the Islamic republic.
It was not immediately clear what had caused the apparent spill, which was located off the island's west coast and appears to cover more than 50 square kilometres, according to global monitor Orbital EOS.
Kharg Island is at the heart of Iran's oil export industry, a lynchpin of the country's battered economy, and lies in the Gulf, north of the narrow Strait of Hormuz.
Following the start of the war on 28 February, Iran largely closed the strait, throwing global markets into turmoil and driving up oil prices.
The US later imposed its own blockade of Iranian ports in response.
Last Sunday, Mr Trump announced a US naval operation designed to reopen the strait to commercial shipping, only to abandon it on Tuesday in favour of a return to negotiations.
Saudi sources said that the kingdom had refused permission for the US military to use its bases and airspace for the Hormuz operation, with one saying Riyadh "felt it would just escalate the situation and would not work".
