Britain and the US are preparing to strike against the Houthis in Yemen to protect shipping in the Red Sea, it is understood.
Cabinet ministers have been invited to a joint call at 7.45pm to discuss the crisis. UK aircraft and Royal Navy ships could take part in any action.
It comes a day after Defence Secretary Grant Shapps hinted action was coming, as he urged Houthi rebels to “watch this space”.
This week, UK and US naval forces destroyed “multiple attack drones” deployed by the Iranian-backed Houthi rebels in the Red Sea, believed to be the largest attack yet from the Yemen-based force.
On Wednesday, Mr Shapps said: “Be in no doubt at all Iran is guiding what is happening there in the Red Sea, providing them not just with equipment to carry out those attacks but also often with the eyes and ears to allow those attacks to happen.
“We must be clear with the Houthis, that this has to stop and that is my simple message to them today and watch this space.”
It follows growing global concern about the disruption in the key global shipping route.
The Houthis claim the attacks are a response to the Israeli bombardment of Gaza
Mr Shapps also posted on Twitter: “Overnight, HMS Diamond, along with US warships, successfully repelled the largest attack from the Iranian-backed Houthis in the Red Sea to date.
“Deploying Sea Viper missiles and guns, Diamond destroyed multiple attack drones heading for her and commercial shipping in the area, with no injuries or damage sustained to Diamond or her crew.
“The UK alongside allies have previously made clear that these illegal attacks are completely unacceptable and if continued the Houthis will bear the consequences.
“We will take the action needed to protect innocent lives and the global economy.”
Antony Blinken, the US Secretary of State, also warned of a response on Wednesday.
“I’m not going to telegraph or preview anything that might happen,” he said
“All I can tell you again, we’ve made clear – we’ve been clear with more than 20 other countries – that if this continues, as it did yesterday, there will be consequences. And I’m going to leave it at that.”
Some major shipping lines and oil giant BP have already diverted vessels around southern Africa, adding time and costs to journeys, rather than risk the Red Sea.
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