Britain is reportedly considering air strikes on Houthi rebels after the US Navy sank three boats that had been targeting a container ship in the Red Sea.
Defence Secretary Grant Shapps said the government would not hesitate to take “direct action” to prevent further attacks on shipping.
It comes after the US military said four boats from Houthi-controlled areas in Yemen fired upon the Maersk Hangzhou and got within metres of the vessel.
Several of the crews of the armed boats were killed, US Central Command said.
Writing in the Daily Telegraph, Mr Shapps said the UK “won’t hesitate to take further action to deter threats to freedom of navigation in the Red Sea”.
“The Houthis should be under no misunderstanding: We are committed to holding malign actors accountable for unlawful seizures and attacks.”
In December, Royal Navy destroyer HMS Diamond joined international efforts to deter attacks on cargo shipping in the Red Sea.
Iran-backed Houthis have claimed the attacks are on ships either linked to Israel or heading to Israeli ports, and say they are aimed at ending the air and ground offensive on the Gaza Strip following the 7 October attacks by Hamas.
On Sunday, UK Foreign Secretary Lord Cameron said he had spoken to Iran’s foreign minister.
In a post on X, he wrote: “I spoke to @Amirabdolahian today about Houthi attacks in the Red Sea, which threaten innocent lives and the global economy.
“I made clear that Iran shares responsibility for preventing these attacks given their long-standing support to the Houthis.”
A UK government spokesperson said: “The situation in the Red Sea is incredibly serious, and the Houthi attacks are unacceptable and destabilising.
“As you would expect, while planning is under way for a range of scenarios, no decisions have yet been made and we continue to pursue all diplomatic routes.
“We call for the Iranian-backed Houthi to cease these illegal attacks and we are working with allies and partners to protect freedom of navigation.”