British Columbia's New Democrat Party said it formally registered opposition to the pipeline with the National Energy Board.
"Under the Enbridge proposal, British Columbia would assume almost all the project's risk, yet would see only a fraction of the benefits," New Democrat leader Adrian Dix said. "By any measure, such a high-risk, low-return approach simply isn't in B.C.'s interests."
The party, in its letter to the NEB, said the planned oil pipeline poses an environmental threat to aboriginal Canadians along the western coast. Greenhouse gas emissions associated with the production of Canadian tar sands oil would contribute to the costs of climate change, the letter said.
Canada wants to send tar sands oil through the planned Keystone XL oil pipeline through the United States or the Northern Gateway pipeline to the Canadian west coast. Environmental groups have described Canada's oil as the dirtiest type of crude oil on the market, however.
"B.C. New Democrats are taking a stand on the Enbridge pipeline because B.C.'s interests are not being adequately represented nor protected by the provincial government in the review process," Dix said.