It has been called the Noah's Ark for seeds, an underground vault in the Arctic to protect the world's crops in the event of a doomsday scenario.

But the Global Seed Vault has reportedly been breached after soaring temperatures made the deep permafrost, designed to provide "fail-safe" protection, disappear.

Meltwater has apparently gushed into the tunnel entrance of the vault, which is buried deep in a mountain on the Norwegian island of Spitsbergen.

“It was not in our plans to think that the permafrost would not be there and that it would experience extreme weather like that,” Hege Njaa Aschim, from the Norwegian government, told The Guardian.

“A lot of water went into the start of the tunnel and then it froze to ice, so it was like a glacier when you went in,” she told the newspaper.