Shipping industry in the dark over US-led Red Sea navy force

Shipping companies remain in the dark over a new international navy coalition being assembled by the United States to combat attacks in the Red Sea.

Few practical details are known about the initiative launched on Tuesday by Washington or whether it will directly engage in the event of further armed attacks at sea.

The Houthi militia in Yemen have since November 19 stepped up attacks on vessels in the Red Sea as Israel's military offensive in Gaza continues.

Their leader said on Wednesday the group would strike US warships if it is targeted by Washington.

Houthi fighters have fired missiles and launched seaborne assaults on ships from fast boats. Missiles fired have been repelled by US warships.

"There are still a number of unknowns with the coalition. We don't know exactly how many warships will be involved, how long it will take those vessels to get to the region, or their rules of engagement and the actual protection scheme that will be put in place," said Corey Ranslem, chief executive of British maritime risk advisory and security company Dryad Global.

"Globally this is a fairly small area, however providing protection to commercial vessels in this region could be a major undertaking depending on the number of vessels along with any changes to the Houthi tactics."

On November 19, Houthi commandos landed on car carrier Galaxy Leader by helicopter and took it back to Yemen's northern Hodeidah port. The vessel and its crew are still being held.

The attacks have disrupted a key trade route that links Europe and North America with Asia via the Suez Canal and caused container shipping costs to rise sharply as companies seek to ship their goods via alternative, often longer, routes.

Dryad's Ranslem said the threat to commercial shipping was likely to continue as the war goes on.

"A number of global shipping companies are diverting around Africa or completely pausing operations within this region. If the coalition efforts are not effective we expect more shipping companies to divert around the Cape," he said.

US Secretary of Defence Lloyd Austin, on a visit this week to Bahrain, home to the US Navy's headquarters in the Middle East, said Bahrain, Britain, Canada, France, Italy, the Netherlands, Norway, Seychelles and Spain were among nations involved in the Red Sea security operation.

The group will conduct joint patrols in the southern Red Sea and the adjacent Gulf of Aden.

The International Chamber of Shipping said it expected the new task force to enable a "co-ordinated effort across a large number of military warships that will provide a significant suppressive response".

A US-led Combined Maritime Force already exists, comprising 39 countries and based in Bahrain. Its main focuses are "counter-narcotics, counter-smuggling, suppressing piracy, encouraging regional cooperation", according to its website.

The new coalition will initially be led by the United States and Britain and other members over time "will be persuaded to do their bit", said Gerry Northwood, a consultant with maritime security company MAST and former British navy captain.