The United Arab Emirates said it was under attack from Iranian missiles and drones on Tuesday, even as Washington said a shaky ceasefire was intact despite an exchange of fire the previous day as US forces attempted to force open the Strait of Hormuz.
The US military said it had destroyed six Iranian small boats, as well as cruise missiles and drones, after President Donald Trump sent the navy to escort stranded tankers through the strait in a campaign he called "Project Freedom".
US Defense Secretary Pete Hegseth said the operation to protect commercial ships was temporary and the four-week-old truce was not over.
"We're not looking for a fight," he told a press conference. "Right now the ceasefire certainly holds, but we're going to be watching very, very closely."
Iran fired missiles at US ships on Monday and attacked the UAE with missiles and drones. Shortly after Hegseth spoke on Tuesday, the UAE's defense ministry said its air defenses were again dealing with missile and drone attacks coming from Iran.
The Gulf state's foreign ministry said in a statement that the attacks were a serious escalation and posed a direct threat to the country's security, adding that the UAE reserved its "full and legitimate right" to respond.
There was no immediate comment on that from Iran, though earlier its parliament speaker, Mohammad Baqer Qalibaf, had said breaches of the ceasefire by the US and its allies endangered shipping through the strait, which carries a large share of the world's oil and fertilizer supplies.
"We know well that the continuation of the current situation is unbearable for the United States, while we have not even begun yet," he said in a social media post.
ATTACKS IN THE GULF
The narrow strait has been virtually shut since the United States and Israel began attacks on Iran on February 28, triggering disruptions that have pushed up commodity prices around the world.
Hegseth said the US had successfully secured a path through the critical waterway and that hundreds of commercial ships were lining up to pass through.
Iran has effectively sealed off the strait by threatening to deploy mines, drones, missiles and fast-attack craft. The United States has countered by blockading Iranian ports and mounting escorted transits for commercial vessels.
The US military said two US merchant ships made it through the strait, without saying when, with the support of Navy guided-missile destroyers.
Iran denied any crossings had taken place, though shipping company Maersk said the Alliance Fairfax, a US-flagged ship, exited the Gulf under US military escort on Monday.
The commander of US forces in the region said his fleet had destroyed six small Iranian boats, which Iran also denied. Iranian media quoted a military commander as saying US forces targeted civilian and cargo vessels, killing five civilians.
Iran also said it fired warning shots at a US warship approaching the strait, forcing it to turn back.
Reuters could not independently verify events in the strait as the two sides issued contradictory statements.
General Dan Caine, the chairman of the Joint Chiefs of Staff, said that since the ceasefire was announced on April 7, Iran had fired at commercial vessels nine times and seized two container ships.
He said Iran has attacked US forces more than 10 times.
However, the attacks fell "below the threshold of restarting major combat operations at this point", Caine told reporters.
Iranian Foreign Minister Abbas Araghchi said peace talks were progressing with Pakistan's mediation, and warned the US and the UAE against being drawn into a "quagmire".
He was travelling to Beijing on Tuesday for talks with his Chinese counterpart, his ministry said.
Iranian drone and missile attacks on the UAE on Monday included one that caused a fire at Fujairah, an important oil port. Iran's state television said military officials had confirmed they attacked the UAE on Monday in response to the "US military's adventurism".
PEACE EFFORTS STALLED
The war in the Middle East has already killed thousands and roiled the global economy. US and Iranian officials have held one round of face-to-face peace talks, but attempts to set up further meetings have failed.
Trump has said the US-Israeli attacks aimed to eliminate what he called imminent threats from Iran, citing its nuclear and ballistic missile programs, its support for Hamas and Hezbollah and its "menacing activities".
Iranian state media said on Sunday that the US had conveyed its response to a 14-point Iranian proposal via Pakistan, and Iran was reviewing it. Neither side gave details.
A senior Pakistani official involved in the talks said "backdoor diplomacy" was continuing. "We have put in a lot of efforts, actually both the sides have narrowed gaps on a majority of the issues," the source said.
Tehran's proposal would defer talks on its nuclear energy and research programs until after agreements to end the war and on shipping security. Trump said over the weekend he was still studying it, but would likely reject it.
Trump has insisted Iran must surrender its enriched uranium stockpiles to prevent it producing a nuclear weapon - an ambition Tehran denies.
