Enbridge’s proposed Northern Gateway plan is, at least for now, dead in the water after Prime Minister Justin Trudeau released a letter of instruction Friday telling his transport minister to ban oil tanker traffic on British Columbia’s north coast.

A ban would prevent hundreds of tankers each year from carrying diluted bitumen extracted from Alberta’s oilsands and piped to northern B.C. from being shipped for export overseas.

“It will mean that Northern Gateway will never happen,” said Gerald Graham, a Victoria consultant specializing in oil spills for more than 40 years.

Graham said it remains to be seen what oil and gas activities will be permitted and which communities could be affected.

“It’s one thing to say what can’t take place, but another to say what will be allowed.”

The moratorium makes official a non-binding motion the House of Commons passed in 2010. It would put the Dixon Entrance, Hecate Strait and Queen Charlotte Sound off limits to tanker traffic in the government’s bid to protect ecologically sensitive areas.

In his letter of instruction, Trudeau told Transport Minister Marc Garneau to “formalize a moratorium on oil tanker traffic on the north coast.”

However, Enbridge indicated later Friday it will still proceed with its pipeline plan.

“We are confident the Government of Canada will be embarking on the required consultation with First Nations and Métis in the region, given the potential economic impact a crude oil tanker ban would have on those communities and Western Canada as a whole,” Ivan Giesbrecht, Northern Gateway’s communications manager, said in a statement.

“Northern Gateway received government approval last year, following the National Energy Board’s careful examination of the project, one of the most exhaustive reviews of its kind in Canadian history.

“Since then, we have been very clear in stating that we have more work to do in establishing respectful dialogues and achieving improved relationships with First Nations and Métis peoples.

“Along with the project’s aboriginal equity partners, we are looking forward to an opportunity to sit down with the new prime minister and his cabinet to provide an update on the progress of our project and our partnerships with First Nations and Métis people in Alberta and B.C.”

The tanker traffic ban will add to the hurdles Enbridge has faced since proposing the pipeline. The project has been met with intense resistance from local communities over concerns including potential spills that could harm fisheries and threaten their livelihood.

A coalition of northerners, environmental groups and First Nations applauded Trudeau’s decision, saying it effectively stops the Northern Gateway plan.

“A legislated oil tanker ban will send a strong message of positive change to all British Columbians, while rebuilding the trust that has been lost over almost a decade in the battle over Northern Gateway,” Caitlyn Vernon, campaigns director at Sierra Club BC, said in a statement. “We want Prime Minister Trudeau to know he has tremendous support for this promise to legally protect B.C.’s north coast from oil tankers.”

ForestEthics advocacy director Karen Mahon said in a statement that the ban effectively ends Northern Gateway.

“Without tankers, crude oil has no place to go. That means no pipelines, no oil trains moving oilsands to the northern B.C. coast.”