The United States has struck Houthi weapons sites in Yemen for the first time using B-2 stealth bombers.

The warplanes targeted five underground storage sites in the strikes, Lloyd Austin, the US defence secretary, said late on Wednesday.

“This was a unique demonstration of the United States’s ability to target facilities that our adversaries seek to keep out of reach, no matter how deeply buried underground, hardened, or fortified,” he said.

Mr Austin said the use of B-2 long-range bombers was an example of “US global strike capabilities”, in what could be seen as a veiled threat to Iran.

While the defence secretary made no reference to the Islamic republic, the warplanes are the only aircraft capable of striking Tehran’s deeply buried nuclear facilities.