What we know about Trump's 'Project Freedom' in Strait of Hormuz

President Donald Trump has announced the US will help "guide" ships that have been stranded by Iran's closure of the Strait of Hormuz. This, he said, was a humanitarian gesture "meant to free up people, companies, and Countries that have done absolutely nothing wrong".

Iran says vessels can only cross it with its authorisation. Iran's military says it has fired at US warships to deter them from trying and the US says it has sunk small boats - threatening a ceasefire meant to end the war.

What does Trump's "Project Freedom" entail and could it lead to a wider resumption of hostilities?

How is the US military implementing Trump's plan?

The Hormuz Strait has remained largely blocked since the US and Israel launched air strikes on Iran on 28 February - and Tehran responded by blocking the crucial waterway through which 20% of the world's oil and liquefied natural gas is meant to pass freely.

An estimated 20,000 sailors and 2,000 ships have been trapped since, according to the International Maritime Organisation - a UN agency that regulates shipping.

There has been growing concern over dwindling supplies and the effects on sailors' physical and mental health.

US Central Command (Centcom) says that "guided-missile destroyers, over 100 land and sea-based aircraft, multi-domain unmanned platforms, and 15,000 service members" are being used to support the operation.

In a briefing on the first day of the operation, Centcom commander Adm Brad Cooper said vessels from 87 countries were stranded in the Gulf - and the US had contacted "dozens of ships and shipping companies to encourage traffic flow through".

What remains unclear is whether the US will attempt to provide stranded ships with a military escort.

Cooper said a "much broader defensive package" than would be required solely to escort ships was on offer, without giving details.

Mick Mulroy, a former US deputy assistant secretary of defence for the Middle East and a veteran of both the Marine Corps and the CIA's paramilitary wing, told the BBC he believed that Project Freedom would be focused on providing air cover and defence from missile and drone attacks - rather than a physical escort of those vessels through the Strait of Hormuz.

However, Mulroy said there was no guarantee it would be successful in helping restore freedom of movement and commerce in the strait.

"The question is whether ships will trust their ability to get through without being attacked, and more importantly, the insurance company," he said.

"If not, the effort will not have the impact we hoped."

Tim Wilkins, managing director at Intertanko, a trade body representing independent tanker owners and operators, told the BBC there was "no structured convoy or co-ordination mechanism in place" and members were asking, "who initiates these transits? Who communicates with the authorities on behalf of the vessel? And, indeed - a critical one - what is the fallback if a vessel is challenged by Iranian forces during the transit?"

Are vessels passing through the Strait of Hormuz?

On Monday afternoon, Centcom said US Navy guided-missile destroyers were operating in the Gulf "after transiting the Strait of Hormuz in support of Project Freedom".

It added American forces were "actively assisting efforts to restore transit for commercial shipping" but gave no details.

"As a first step, 2 U.S.-flagged merchant vessels have successfully transited through the Strait of Hormuz and are safely headed on their journey," Centcom also said. Again, no details were released about the identity of the commercial vessels.

Shipping company Maersk did confirm that one of its vessels had been able to exit the Gulf, accompanied by the US military.

But Iran's powerful Islamic Revolutionary Guard Corps denied any vessels had passed through the Strait.

Is Iran firing at US warships and other vessels?

Hours after the US operation was meant to have begun on Monday, the Iranian military said it had fired against "American and Zionist enemy destroyers", which it said the Americans had "disregarded".

Centcom quickly denied the Iranian claims that one of its warships had been hit by two missiles.

According to Centcom, Iran did fire cruise missiles at both US warships and US-flagged commercial ships, while drones and small boats were used against commercial ships.

In a post on Truth Social, Trump also said Iran had "taken some shots" at "unrelated nations".

The United Arab Emirates (UAE) - a Gulf ally of the US, which has often been attacked by Iran during the war - said a tanker affiliated with Adnoc, its state-owned oil company, had been targeted by two drones as it transited the Strait of Hormuz.

No-one was injured, the country's foreign ministry said in a statement. At least three missile interceptions were also reported.

A suspected strike also hit a South Korean cargo vessel anchored in the Strait of Hormuz, in waters near the UAE.

Centcom commander Cooper said that some of the US attack helicopters supporting the mission had been used to sink six small Iranian boats that were targeting civilian vessels. Iran has denied this.

Is the Iran war resuming?

Grant Rumley, a Middle East expert who served as an adviser to both the Biden and Trump White Houses between 2018 and 2021, said that securing passage for all the ships in the Gulf would be "very, very hard".

Doing so, he says, may require a stronger, more "kinetic" military option - a possibility he views as likely.

"I think that the general consensus is that a resumption of hostilities is a question of when," he said. "Not if."

Nitya Labh, a fellow on the International Security Programme at London's Chatham House, said the US operation was "extremely risky".

"I think what's happening is quite escalatory, it suggests the US isn't willing to negotiate over the terms of reopening the Strait," she told the BBC.

"The US has accepted that the only way to continue to move shipping is under the threat of force or strikes from Iran," Labh said.

She added that, even if President Trump's "Project Freedom" succeeded in getting some vessels out of the Hormuz Strait, "it will be a temporary relief at best" - a more sustained effort would be required to open up the critical waterway.