Photo: CTV News

A B.C. First Nation is promising a legal challenge of the federal government's decision to approve the Trans Mountain pipeline expansion, while the premier says his government will continue to defend the province's coast.

Environment Minister George Heyman told a news conference Tuesday that tens of thousands of jobs and billions of dollars in economic activity are at risk from a bitumen spill.

"Let me say to British Columbians who value our environment, who cherish our coast, who expect their government to stand up for their interests, we will not abandon our responsibility to protect our land and our water," Heyman said.

Chief Leah George-Wilson of the Tsleil-Waututh Nation said it will appeal Ottawa's decision to the Federal Court of Appeal. The First Nation was among those that won a legal challenge of the project last August.

"The federal decision to buy the pipeline and become the owner makes it impossible to make an unbiased, open-minded decision," she told a news conference on Musqueam territory.

Prime Minister Justin Trudeau's government has purchased the pipeline and expansion project for $4.5 billion. Construction was paused in August after the Federal Court of Appeal struck down the government's approval, citing the National Energy Board's failure to consider the marine impacts and inadequate First Nations consultation.

After an energy board review of the effects on marine life and further Indigenous consultation, the federal cabinet announced Tuesday it was approving the project for a second time.

The expansion will triple the capacity of the existing Trans Mountain pipeline, which runs from the Edmonton area to Burnaby, B.C., and increase tanker traffic in Burrard Inlet seven-fold.

George-Wilson and other Indigenous leaders said Ottawa failed to meaningfully consult or gain consent from First Nations despite the Appeal Court's ruling.

Squamish Nation Coun. Khelsilem said it is also prepared to fight the decision in court. The Squamish only received some information from Ottawa after the deadline for responses passed, he said, calling the consultation process a "failure."

"After that deadline, they provided us with more information that we were unable to even comment on because their self-imposed deadline had already passed," he added.

Chief Dalton Silver of the Sema:th First Nation said the energy board has imposed a condition on Trans Mountain that says the Crown corporation must negotiate with it for access to its traditional territory, including a sacred burial site in Abbotsford.

"That condition has not been met," he said. "Should any equipment come onto that site, we'll be there to meet them."

Others said they are preparing for a busy summer of opposition. Grand Chief Stewart Phillip of the Union of B.C. Indian Chiefs said the decision, while not surprising, "will breathe new life into the resistance."

Premier John Horgan said he spoke with Trudeau before the decision and reiterated his concerns about the potential of a marine spill.

Asked whether he would support any lawsuits filed against the project, Horgan said he'd have to look at the substance of the applications.

"If it's in the interests of British Columbia to join them, we will," he said.

Horgan said his government is pursuing a reference case in the Supreme Court of Canada that asks whether B.C. has the power to restrict oil shipments through its territory, which it lost at the B.C. Court of Appeal.

Several hundred protesters gathered Tuesday evening in downtown Vancouver carrying signs that read "Justin the hypocrite," and "No jobs on a dead planet." Many pledged further action to block the project from being built.