Britain has said it remains involved in discussions with the US and European allies over escorting merchant shipping through the strait of Hormuz but the situation remains too dangerous for it to happen soon.
Iran is still considered to pose a threat and to have a wide range of weapons available – from cruise missiles to sea drones – despite 19 days of US-led bombing of its navy and coastal sites.
A UK defence official said Tehran had “a very effective kind of disaggregated command and dispersal system”, meaning it could continue to attack even though many of its military and political leaders have been killed.
Its mountainous coastline makes surveillance of missiles and drones difficult. The defence official added: “The level of threat is such that I don’t see many nations being willing to put warships into the middle of that threat right now.”
Iran has in effect closed the strait with periodic attacks on oil tankers and other shipping. About a fifth of seaborne crude oil traffic passed through the strait before the war, and a dramatic fall in exports has helped push prices above $100 a barrel.
Donald Trump has criticised the UK and other Nato members for failing to offer warships to help patrol the strategic waterway. On Truth Social on Tuesday he said the United States “no longer ‘need’ or desire the Nato Countries’ assistance”.
However, the UK said contacts continued about the issue at a military level, and additional British planners had been dispatched to liaise with US Central Command (Centcom), which is leading the American military effort against Iran.
It is unclear what the UK would contribute to any maritime escort operation, though the Royal Navy could in theory redeploy HMS Dragon, a destroyer currently en route to Cyprus, into the Arabian sea. No other warships are immediately available.
On Wednesday, John Healey, the defence secretary, discussed the strait of Hormuz in a call with the defence ministers of France, Germany, Italy and Poland. France has previously said it would be willing to send warships to the strait, but only when the “most intense” phase of the conflict is over.
Al Carns, a UK junior defence minister, said the last escort operation in Gulf, which began in 1987 during the last phase of the Iran-Iraq war, required 30 warships. “That gives you just an example of the resources required. So it’s a major undertaking,” he said in a briefing.
He emphasised “this must be a multinational solution”, arguing that Britain had no choice to work with the US, however difficult. “But I would say this: there is one thing worse than working with allies and that’s working without them,” he said.
The US navy has so far not indicated it is ready to become involved in an escort operation, preferring to focus on the continuing bombing campaign, though officials have suggested that could change next month. The Abraham Lincoln carrier strike group is operating off the coast of Oman.
Overnight, Centcom said it had used 5,000lb “bunker buster” bombs on what it said were “hardened Iranian missile sites along Iran’s coastline near the strait of Hormuz”, part of a wider attempt to eliminate the threat from anti-ship cruise missiles.
Kevin Rowlands, a naval expert with the Royal United Services Institute thinktank, said that while Iranian capacity to inflict damage was being steadily reduced, danger to shipping remained.
“It is almost impossible to reduce the risk to zero and we can expect ships to face a residual level of threat for some time to come,” Rowlands said, adding that the narrow, 20 nautical mile width of the strait “effectively creates a kill zone” where the warning time for an attack may only be a few seconds.
