The proposal by TransCanada Corp. to construct a pipeline carrying oil from western Canada to Quebec refineries, and then on to the East Coast for possible export to Asia, would receive a "rigorous" analysis before receiving government approval, Harper told a news conference in Quebec City.
Harper gave a measure of initial support for the $12 billion project by calling pipelines a safer way than railroads to ship crude.
A train hauling tank cars of crude derailed and exploded in Lac-Megantic, Quebec, last month, resulting in a fire and explosion that killed at least 47 people and destroying several buildings.
"I think the reality of anybody who looks at the business (is) that the absolute safest way to transport energy products is through pipelines," Harper said. "That's the safest way you can go."
Harper said the analysis of the proposed TransCanada Energy East pipeline would be independent and would have a significant influence on the government's decision on approval of the project, the Montreal Gazette said.
"Obviously we think it is a good idea in principle in terms of selling our energy products," he said.
TransCanada said in a written statement it planned to convert a long stretch of its natural gas pipeline to liquid crude and then add approximately 1,400 kilometers (870 miles) of new pipe that, when completed, would pump about 1.1 million barrels of crude per day from Saskatchewan and Alberta, through Quebec and on to New Brunswick, where it would be used by eastern Canada refineries or exported to overseas markets from a new deep-water terminal being built in Saint John.
TransCanada said it had long-term contracts in place for roughly 900,000 barrels per day to be delivered to refineries and export terminals.
TransCanada President and Chief Executive Officer Russ Girling said the Energy East project would add additional certainty to western Canadian oil producers.
"But the industry also requires additional pipelines such as Keystone XL to transport growing supplies of Canadian and U.S. crude oil to existing North American markets," he said. "Both pipelines are required to meet the need for safe and reliable pipeline infrastructure and are underpinned with binding, long-term agreements."