Experts believe western allies most likely to target coastal sites in attempt to halt spate of Houthi attacks in Red Sea
Middle East crisis – live updates
Britain and the US are poised to launch strikes against Houthi military targets in Yemen, as the leader of the rebel group promises to respond to any assault with fresh attacks on shipping in the Red Sea.
Western defence sources indicated preparations were intensifying on Thursday in response to a Houthi attack of 21 missiles and drones aimed at US and UK warships on Tuesday night, although its scale and timing remain secret.