A $20m appeal to recover 1.1m barrels of crude from a decaying vessel off the coast of Yemen has raised just $100,000, amid growing fears of an environmental catastrophe in the Red Sea.

The United Nations aimed to raise the last of the $80m needed by the end of June to start emptying the 407,000-dwt FSO Safer (built 1976) that is at imminent risk of leaking and devastating the coastlines of Yemen and neighbouring states.