NDP Leader Tom Mulcair maintains the Northern Gateway pipeline will never get built, a day ahead of the National Energy Board's report on the Enbridge project.
A panel reviewing the environmental effects of the pipeline is expected to make public its recommendations for the project on Thursday in Calgary.
"We will maintain our firm opposition to the Northern Gateway pipeline," Mulcair told reporters during a year-end news conference in Ottawa on Wednesday.
'You can't just ... say, "This is going through." This is the Conservative way and, by the way, that's why Northern Gateway is never going to get built.'- NDP Leader Tom Mulcair
If approved, the pipeline would transport oil from Alberta to Kitimat, where it would be moved through tankers in the Douglas Channel.
"Allowing super tankers into the Douglas Channel is madness, and it should not take place," Mulcair said.
Aside from the risk of spills, Mulcair said the federal government has failed to consult First Nations that would be impacted by the project.
"The pipeline itself suffers from one major flaw, which is the fact that we're not dealing with First Nations a nation-to-nation basis," Mulcair said.
"We should never have wasted public money on this study," the NDP leader added.
"You can no longer impose these things from the top down. This is another era. You need social adhesion, you need to work with people. You can't just bark at them and say, 'This is going through.'
"This is the Conservative way and, by the way, that's why Northern Gateway is never going to get built."
The Joint Review Panel wrapped up almost 18 months of public hearings throughout B.C. and Alberta in June.
The fate of the pipeline rests with the federal government which has up to 180 days to decide whether it ought to be built once the joint panel issues its report.