President Donald Trump has announced the US will help "guide" ships that have been stranded by Iran's closure of the Strait of Hormuz.

The Strait has remained largely blocked since the US and Israel launched air strikes on Iran - 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.

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The president said the US had been asked by countries "from all over the World" to help free up their ships which were "locked up in the Strait of Hormuz" and were "merely neutral and innocent bystanders!".

And so, in response, the US would "guide their Ships safely out of these restricted Waterways".

"The Ship movement is merely meant to free up people, companies, and Countries that have done absolutely nothing wrong โ€” They are victims of circumstance," Trump said in the post on his Truth Social platform.

He added this was "a Humanitarian gesture on behalf of the United States, Middle Eastern Countries but, in particular, the Country of Iran" - as many of these vessels were "running low on food, and everything else necessary for largescale crews to stay on board in a healthy and sanitary manner".

Trump's announcement appears mild compared to previous statements against Iran.

It even makes it sound like Iran is a party to the operation - the president went as far as to say "Project Freedom" was being undertaken on behalf of Iran, too.

But that is not how Iran sees the operation.

A statement from the head of Iran's central command said it would attack "any foreign armed force" that tried to approach or enter the Strait, "especially, the aggressive US army".

Maj Gen Ali Abdollahi said that Iran had "repeatedly" stated that the Hormuz Strait "is under the control" of the Iranian armed forces, and safe passage through it must be co-ordinated with it "under all circumstances".

An estimated 20,000 sailors and 2,000 ships have been trapped in the Gulf since the start of the war with Iran, 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.

But Trump did not say how they would be able to sail away - he only threatened to use force "if, in any way, this Humanitarian process is interfered with".

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

The statement did not specify how the combined hardware and personnel would support the vessels.

If the US guidance was meant as an offer of information and advice to vessels and crew, that may be of little help given Iran's ominous threats to attack them.

If, on the other hand, the US will attempt to provide stricken ships with a military escort, that could bring them back into direct military confrontation with Iran.

Hours after the US operation was meant to have begun, the Iranian military said: "With a firm and swift warning from the Islamic Republic Navy, the entry of American and Zionist enemy destroyers into the Strait of Hormuz was prevented."

Not long afterwards, Centcom denied Iranian claims that one of its warships had been hit by two missiles.

The United Arab Emirates - 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.

It is not clear if the tanker's movements enabled by the US as part of "Project Freedom".

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.

Iran has severely limited traffic through the Strait since the war began - with only a handful of vessels allowed through, mainly from allies of Tehran.

A ceasefire is currently in place that is meant to enable the sides to reach a deal to end hostilities, but there has been little progress.

Iran has forcefully objected to the US enforcing a naval blockade on Iranian ports.

The BBC spoke on Sunday to oil tanker captain Ramoon Kapoor, who is one of those trapped - he described witnessing "various attacks, various missiles, explosions" and said the situation had been "pretty tense".

He also said his crew had experienced significant stress and anxiety.

The UK Maritime Trade Operations Centre has warned ships attempting to transit the Strait of Hormuz that they face "critical" security threats" due to "ongoing regional military operations", as well as "the proximity and dangers of any reported mines or threats along intended transit routes".

Trump announcements during the current conflict have often moved markets - particularly the price of oil.

But his announcement of "Project Freedom" drew no immediate reaction.

There was a quick spike following Iran's claim of hitting a US warship and the US's subsequent denial, but - by and large - the price of a barrel of Brent crude has remained well over $100 (ยฃ74) - more than 50% higher than before the war.

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