"This sale is premature due to the absence of a ... plan that would protect sensitive habitats, which polar bears, beluga and bowhead whales need for their survival," Peter Ewins, the group's director of species conservation, said at a news conference.

"In addition, there is no proven technique for recovering oil spills in such dangerous ice waters," he said.

Earlier this month, Canada, which is home to two-thirds of the world's 25,000 polar bears, said it would soon list the animals as a species of special concern.

Ewins said the polar bear population in the southern Beaufort Sea was showing clear signs of distress.

No one from the Canadian federal Indian affairs and fisheries ministries -- who share responsibility for the Beaufort Sea -- was immediately available for comment.

Environmental groups in the United States are suing Washington over its decision to sell oil and gas rights in the Chukchi Sea off Alaska's northwest coast.