(CNN)The United Nations has released a plan to offload 1 million barrels of oil off a rusting supertanker that has been moored off the coast of Yemen for more than 30 years.
In an attempt to avert what could be one of the worst environmental disasters in history, a very large crude carrier was purchased by the UN to get the oil off the FSO Safer.
The 47-year-old tanker has not been maintained since 2015 because of the conflict in Yemen, the Administrator of the United Nations Development Programme (UNDP) Achim Steiner told a briefing on Thursday.
"A massive spill from the Safer would destroy pristine reefs, coastal mangroves and other sea life across the Red Sea, expose millions of people to highly polluted air, and cut off food, fuel and other life-saving supplies to Yemen, where 17 million people already need food aid," the UN said on a website dedicated to the issue.
A cleanup from the oil spill would cost $20 billion and would affect 200,000 communities with their livelihoods "wiped out," UN's Resident and Humanitarian Coordinator for Yemen, David Gressly, said.
It could touch the African coast, it affect shipping and would cause damage in pristine waters that would not recover for 25 years, Gressly added.
The UN said the FSO Safer supertanker is holding four times the amount of oil spilled by the Exxon Valdez which is "enough to make it the 5th largest oil spill from a tanker in history."
The new $55-million double hull crude carrier will attempt to move the oil off the FSO Safer in a 'ship-to-ship' transfer in May, Steiner said.
The operation has been described by Gressly as "high risk" and "highly complex." "We're not quite there yet," Gressly said, adding that they have already mobilized $95 million for the project but need $34 million more to complete it.
Where the oil will end up after its removed is yet to be decided, but discussions are ongoing, Steiner added.