Donald Trump has posted video footage of a military strike on Houthi rebels, as the cost of US bombing in Yemen nears $1 billion (£780 million).

“These Houthis gathered for instructions on an attack,” Mr Trump wrote alongside the black-and-white aerial footage said to show an air strike on the Iranian-backed group.

“Oops, there will be no attack by these Houthis. They will never sink our ships again,” the US president wrote.

The 25-second clip showed a group starting to gather, before an explosion left only two trucks visible and a deep crater in the ground, as smoke cleared.

Yahya Saree, a Houthi spokesman, denied the gathering was linked to the rebels.

He said: “Does the US take pride in such an act? This was a tribal gathering that had nothing to do with your ships.”