As environmentalists bemoan the Liberal government's promise to build the Trans Mountain pipeline expansion project, Ottawa handed them a victory of sorts last night with the passage of a tanker moratorium bill that will prohibit tankers carrying crude oil from loading or unloading at ports in northern British Columbia.

Bill C-48, which passed the House of Commons along party lines and is now headed to the Senate for its second legislative phase, was introduced after Prime Minister Justin Trudeau and his cabinet vetoed Enbridge's Northern Gateway pipeline — a project that would have carried crude from Alberta through northern B.C. to a tanker terminal in Kitimat for export to Asia.

At the time, Trudeau said it would be a mistake to move crude through the pristine Great Bear rainforest, describing the region as the "jewel" of B.C.

The legislation — which would ban tankers capable of carrying more than 12,500 metric tons of oil from an area that stretches from the northern tip of Vancouver Island to the Alaska border — has been both celebrated and pilloried by local Indigenous peoples.

The failed Northern Gateway project had secured financial agreements with some 21 First Nations along the project's route — an entity called Aboriginal Equity Partners owned a 33 per cent stake in the line — while others Indigenous communities were worried about the potential for a spill in coastal waters.

Environmentalists championed C-48's passage Wednesday because it would effectively prevent another project like Northern Gateway.

An oil tanker anchors at the terminus to the Kinder Morgan Trans Mountain pipeline in Burnaby, B.C. (Chris Corday/CBC)

"It's a significant win for the coast that the oil tanker moratorium has finally reached this point, and we wish it swift passage through the Senate," Jessica Clogg, executive director of the West Coast Environmental Law Association, said in a statement. "This is a big step forward for keeping north coast ecosystems, communities and livelihoods safe from the risk of oil spills."

But an Indigenous-owned company called Eagle Spirit — which hopes to build a 1,500-km pipeline that would carry up to two million barrels of crude per day from near Fort McMurray to tidewater — has already launched legal action in a B.C. court to stop Bill C-48.

"We absolutely do not support big American environmental NGOs (who make their money from opposing natural resource projects) dictating government policy and resource developments within our traditional territories," the chiefs council opposing Bill C-48 recently wrote on a GoFundMe page created to raise money to cover their legal costs.

"We support the First Nations-led Eagle Spirit Energy energy corridor because it would provide real-world sustainable benefits and own-source revenue and meaningful participation for the poorest communities in Canada through a project whose outcomes cannot be duplicated by government."

People in western Canada just cannot understand the government ... it keeps chopping off the hand that feeds it. It is so sad. - Conservative MP Randy Hoback

Proponents of Eagle Spirit say the government didn't properly consult with Indigenous communities before introducing the bill — a complaint typically heard from Indigenous people looking to block natural resources development.

Trudeau instructed Transport Minister Marc Garneau to implement the tanker ban in his initial mandate letter, which was released before the department began consultations with Indigenous people in the area.

If the tanker ban is enacted, the $16 billion Eagle Spirit project would have to be either shelved or rerouted over the Canada-U.S. border to Hyder, Alaska, where no such tanker ban has been contemplated.

The proposed route for the Eagle Spirit Energy Pipeline would run about 1,562 kilometres from Fort McMurray to a terminal at either Grassy Point, B.C. or Hyder, Alaska. (Eagle Spirit Energy)

Conservative MPs said the tanker moratorium is further proof the Liberal government is anti-pipeline.

"Let us not fool ourselves. This is not a tanker ban. This is to stop development in the resource sector and to stop shipping products to the West Coast," Saskatchewan MP Randy Hoback said.

"It is what the Liberals really planned to do from day one, and this bill is how they are going to achieve it. That is very disappointing.

"People in Western Canada just cannot understand the government ... it keeps chopping off the hand that feeds it. It is so sad."

Garneau said this "historic" bill accomplishes the government's environmental priorities and simply formalizes an existing voluntary tanker exclusion zone.

"These strong measures against potential oil pollution are what Canadians want and expect," he said during an appearance before the Commons transport committee.

"The oil tanker moratorium will allow us to preserve this precious ecosystem for the enjoyment and benefit of future generations. We have an opportunity now to accomplish something of historic importance. And we should grasp that opportunity."

The bill must next pass the Senate before becoming law.