Enbridge aims to construct the Northern Gateway oil pipeline to deliver so-called tar sands oil to ports in British Columbia for export to Asian markets.
Critics of tar sands point to a series of oil spills, including a 20,000-barrel spill by Enbridge in Michigan in 2010, as reason for caution.
British Columbia Premier Christy Clark laid out criteria that need to be met before the provincial government gets behind the project.
Canadian Prime Minister Stephen Harper said, during a speech in Vancouver, that science would drive decisions on national oil pipelines.
"The only way governments can handle controversial projects of this manner is to ensure that things are evaluated on an independent basis scientifically, and not simply on political criteria," he was quoted by the Calgary Herald as saying.
Enbridge spokesman Todd Nogier said he was pleased with Harper's declaration.
"To the extent that (the prime minister) has expressed that the regulatory process is to be based on science and fact, we're quite comfortable," he was quoted as saying.