Canadian Prime Minister Stephen Harper is in New York to lay out his case for the Keystone XL pipeline. His visit follows a similar trip last month by Alberta Premier Alison Redford.
Pipeline company TransCanada wants to build Keystone XL to carry so-called oil sands from Alberta to southern U.S. refineries. The cross-border pipeline needs the U.S. government's approval.
Harper told The Council on Foreign Relations the project should move forward because it was vetted thoroughly in an environmental analysis by the U.S. State Department.
"The only real immediate environmental issue here is that we want to increase the flow of oil from Canada via pipeline or via rail," he said. "If we don't do the pipeline, more and more is going to be coming in via rail, which is far more environmentally challenging in terms of emissions and risks and all kinds of other things than building a proper pipeline."
The State Department's review said emissions tied to the production Canadian crude oil would be prevalent with or without Keystone XL. Rail deliveries should be considered when weighing Keystone's national interest, however.
Rail deliveries of crude oil have increased in the United States because of a lack of pipeline capacity. Spills from rail are more common, but less severe, when compared with pipelines.