Keystone oil pipeline remains shut after spill in North Dakota

April 9 (Reuters) - The Keystone oil pipeline from Canada to the United States remained shut on Wednesday following an oil spill near Fort Ransom, North Dakota, and "return to service" plans are being evaluated, its operator South Bow SOBO.TO said.

The 4,327-km (2,689-mile) pipeline, a major conduit for crude oil supply from Alberta to U.S. refineries in Illinois, Oklahoma and along the U.S. Gulf Coast, was shut on Tuesday.