ADEN, Yemen, March 2 (Reuters) - The UK-owned Rubymar, attacked by Houthi militants last month, has sunk in the Red Sea, Yemen’s internationally recognised government said on Saturday, warning of an “environmental catastrophe” from the ship’s cargo of fertiliser.

If confirmed, it would be the first vessel lost since the Houthis began targeting commercial shipping in November, forcing shipping firms to divert vessels on to the longer, more expensive route around southern Africa.

The Iranian-backed Houthis, who control the north of Yemen and other large centres, say they are acting in solidarity with Palestinians in Gaza.

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