The United Nations has announced a $5 million crowdfunding campaign to help prevent the imminent breakup of an aging supertanker that holds over a million barrels of oil — four times the amount spilled in Alaska by the Exxon Valdez in one of the world’s worst ecological disasters.

If the FSO Safer, moored off the coast of Yemen, breaks up or explodes, the resulting oil spill would ravage pristine reefs, coastal mangroves, and other sea life across the Red Sea; cause massive air pollution throughout the region; likely force the Hudeidah and Saleef ports to close, cutting off supplies to war-torn Yemen, where 17 million people already need food aid; and choke the movement of vessels through some of the world’s busiest shipping lanes.

It would take 25 years for fish stocks to recover, cost $20 billion to clean up, and deprive coastal communities of their income from fishing for years, the UN has warned.

“The United Nations is ready to implement an emergency operation to prevent this disaster,” a UN statement said. “But the work to transfer the oil to a safe vessel is already delayed because of insufficient funding.”

The UN estimates that it needs $144 million to deal with the ship, of which $80 million would be for the emergency transfer of oil to a temporary storage site. The rest would finance a permanent replacement of the ailing vessel.