Harper was visiting the Irving Oil refinery in Saint John, where he said the TransCanada (TSX:TRP) pipeline would benefit consumers in Atlantic Canada, a region that depends on foreign sources of oil.
"We're not just expanding our markets for our energy projects, which we need to do," said Harper, seated next Premier David Alward and Irving Oil chairman Arthur Irving.
"We are also at the same time making sure that Canadians themselves benefit from those projects and from that gain energy security."
The Energy East pipeline project, which still has to clear regulatory reviews, would deliver up to 1.1 million barrels per day from Western Canada to Quebec in late 2017. A 1,400-kilometre extension would be built to ship oil to Saint John a year later.
Some experts have expressed doubt that the pipeline would have much impact on the region's fuel market, saying that energy companies are eager to ship their oil at the ice-free, deepwater port in Saint John because it would enable them to access more lucrative markets overseas by tanker.
The $12-billion development has the support of the Alberta and New Brunswick governments, but the minority Parti Quebecois government of Pauline Marois has remained noncommittal on the proposal.
Harper prefaced his remarks by saying the federal government will remain independent from the project and ensure it is properly regulated. But he also repeatedly said the idea was "exciting" and praised the private sector's efforts to make it a reality.
"It's a project that will assure all of Canada will benefit from our energy industry," he said.
"We will have a large amount to sell to the world, but for the first time we will have the capacity to sell our own products to our citizens."
Irving Oil has said it plans to construct a $300-million marine terminal to expand shipping, a decision prompted by the private sector interest in the west-to-east pipeline project as announced by TransCanada last week.
Environmental groups have cautioned the proposal poses a fresh set of risks to the country's water supply if spills occur. First Nations groups have also expressed concerns about the project, saying they will not support it unless environmental protection and aboriginal and treaty rights are guaranteed.
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