UNITED NATIONS, June 13 (Xinhua) -- The United Nations on Monday launched a crowdfund campaign to avert oil spill from the decaying FSO Safer that is moored in the Red Sea north of the Yemeni city of Hodeidah, a UN spokesman said.

The UN resident coordinator and humanitarian coordinator for Yemen, David Gressly, on Monday announced the launch of a social media campaign "to raise the necessary funds to start the emergency operation to transfer the oil from the FSO Safer to a safe temporary vessel," Stephane Dujarric, spokesman for UN Secretary-General Antonio Guterres, said at the regular press briefing.

"Following Saudi Arabia's announcement of a 10 million U.S. dollars pledge on June 12 and the United States' announcement that it is working towards a 10 million dollars contribution, the world body now has three-quarters of the 80 million dollars required to start the emergency operation," said Dujarric.

A May 11 pledging conference, co-hosted by the Netherlands and the United Nations, raised around 40 million dollars of the funds needed.

According to the United Nations, the overall estimated cost of the UN plan is about 144 million dollars, including the long-term replacement of the floating storage and offloading (FSO) vessel.

The decaying, dilapidated supertanker has been described as a "floating time-bomb" that risks causing an explosion or an oil spill four times as disastrous as the 1989 Exxon Valdez incident in the Red Sea.

As flammable gasses continue to build up in the ship's chambers and its structural integrity deteriorates, efforts to take it off the water are becoming increasingly urgent, according to the United Nations.

The Safer has been moored in the Red Sea since 1988.

The Houthis have been blockading UN efforts to inspect and maintain the vessel after the war between the group and the Yemeni government began in 2014.