SAN FRANCISCO -- As political maneuvering continues over the fate of the controversial proposed Keystone XL pipeline, one of the world's largest energy companies -- BP -- is already signaling the direction it plans to take: it's positioning itself to tap the burgeoning supply of Canadian tar sands oil.

BP announced it will divest from its oil refineries on the Southern West Coast -- in Carson, Calif. -- and Texas City, TX, and expand its operations in the Pacific Northwest and the Midwest -- a move that would halve the company's U.S. refining capacity.

David Hackett of Stillwater Associates, an energy consulting firm based in Irvine, Calif., called the energy giant’s exit from California “a big deal.”

“There hasn’t been a major refinery sale in California since the late nineties,” he said, adding that the divestment appears to be “an investment decision that BP has made,” rather than being driven by refinery consolidation or government action.