A “floating time bomb” oil tanker left adrift in the Red Sea has successfully been drained of its cargo, the UN says.

The vessel was abandoned off Yemen in 2015 after war broke out with more than one million barrels of oil on board.

It was feared the deteriorating FSO Safer could explode or break apart, causing a major spill.

The UN said environmental disaster had been averted but it is unclear how the oil’s sale will be agreed between warring sides.

German Foreign Minister Annalena Baerbock said the international community had “defused a floating time bomb and prevented a potentially enormous environmental and health disaster”.

The UN led a $120m (£95m) fundraising effort to secure the decaying ship and buy another tanker to take the recovered oil.

It took 18 days to complete the transfer in a stretch of water where naval mines were known to be located.

The FSO Safer was constructed in 1976 and was carrying more oil than was spilled in the 1989 Exxon Valdez disaster when it was left at sea.

It is anchored near the Ras Isa oil terminal, which is controlled by Yemen’s rebel Houthi movement.

The group is still fighting a Saudi-led coalition in a conflict that has devastated much of the country.

Work is set to begin on the difficult task of decontaminating and scrapping the vessel but the fate of the recovered oil – which is majority owned by Yemeni state firm SEPOC – may prove even more complex to resolve.

There is no agreement on how profits from the oil’s sale will be shared among warring groups.

UN development programme administrator Achim Steiner said: “The best end to the story will be when that oil actually is sold and leaves the region altogether.”