A UK-owned ship attacked by Houthi militants last month sank in the Red Sea, the U.S. military confirmed on Saturday, as it echoed a warning from Yemen's internationally recognised government that the vessel's cargo of hazardous fertiliser posed a risk to marine life.

The Belize-registered Rubymar is the first vessel lost since the Houthis began targeting commercial ships in November. 

Those drone and missile assaults have forced shipping firms to divert ships to the longer route around southern Africa, disrupting global trade by delaying deliveries and sending costs higher.

The sinking bulk carrier also "presents a subsurface impact risk to other ships transiting the busy shipping lanes of the waterway," U.S. Central Command (CENTCOM) said in its statement on social media platform X.

The Iran-aligned Houthis, who control the north of Yemen and other large centres, say their campaign is a show of solidarity with Palestinians in Gaza.

The Houthi attacks have prompted a series of strikes against their positions by the United States and Britain, and have led other navies to send vessels to the region to try to protect the vital Suez Canal trade route.

The Rubymar went down in the southern Red Sea late on Friday or early on Saturday, according to statements from the Yemen government and CENTCOM.

The U.S. military previously said the Feb. 18 missile attack had significantly damaged the bulk vessel and caused an 18-mile (29-km) oil slick. The ship was carrying about 21,000 metric tons of fertiliser, CENTCOM said on Saturday.

Ahmed Awad bin Mubarak, the foreign minister in Yemen's internationally recognised government in Aden, said in a post on X: "The sinking of the Rubymar is an environmental catastrophe that Yemen and the region have never experienced before.