New York: Crude oil climbed above $80 a barrel for the first time in six weeks as freezing weather and improving economic prospects around the world bolstered the outlook for fuel demand.

US heating oil supplies may drop for a seventh week after a cold weather system moved into the Northeast. Beijing and Seoul were hit by the heaviest snowfall in more than a half century. Oil also rose as China's manufacturing expanded at the fastest pace in more than five years.

"All of the news today is bullish," said Michael Lynch, president of Strategic Energy & Economic Research in Winchester, Massachusetts.

"Record cold weather both here and in Asia is certainly going to boost fuel demand. The economy isn't looking so bad anymore, which is also positive for demand."

Crude oil for February delivery rose $1.89, or 2.4 per cent, to $81.25 a barrel at 9.47am on the New York Mercantile Exchange.