Green Party Leader Elizabeth May has vowed to do everything in her power to stop Kinder Morgan’s Trans Mountain Pipeline from being built -- and she’s willing to spend time behind bars.

In an impassioned exchange on CTV’s Power Play moments after Prime Minister Justin Trudeau announced his government’s approval of the project -- along with Line 3 -- May swore that the “as long as there’s breath in my body, I’ll fight this damn thing.”

“Of course I’ll go to jail. I’ll block pipelines, I’ll stand shoulder-to-shoulder with First Nations. This is not an issue you compromise on,” said May, a Vancouver Island MP and longstanding voice among Canadian environmentalists.

“We are not giving up. This is a terrible blow and a betrayal. But we do not give up.”

The major announcement on Tuesday afternoon is one of the most pivotal policy decisions since Trudeau’s government took office last fall, and is already being heralded as an economic boon by Alberta Premier Rachel Notley. Kinder Morgan’s $6.8-billion Trans Mountain pipeline expansion, from Alberta to Burnaby, B.C., and Enbridge’s $7.5-billion Line 3 pipeline replacement, from Alberta to Wisconsin, would increase the province’s pipeline capacity by more than 1.1 million barrels per day and create thousands of jobs.

The Liberal government also said it will block the Northern Gateway project, which would’ve seen a pipeline cross through the Great Bear Rainforest to Kitimat, B.C., and make good on its campaign promise to introduce a tanker moratorium in B.C.’s northern waters.

For May, the most serious concerns come from a boost in tanker traffic along B.C.’s southern coast, which she estimates will increase seven-fold thanks to the Trans Mountain project and threaten tourism, the fishing industry and B.C.’s southern resident killer whale population.

“It’s not a question of if there will be a spill, it’s when there will be a spill,” May said.

May said the type of oil product being carried through the pipeline – a mixture of bitumen and a diluent -- is also cause for concern because “there is no evidence that you can clean up a spill” of that type.

Conservative Interim Leader Rona Ambrose said “thousands of jobs” have been lost with the rejection of the Northern Gateway project, and said she doubts the Liberal government can follow through on the Trans Mountain pipeline project.

“With Kinder Morgan, what I will say is that I don’t think that this pipeline will be built,” Ambrose told reporters in a briefing after the announcement. “I think that the protests will ensue, the fight is on. And so I think today what we saw is one project be rejected -- which is 4,000 jobs (lost) -- and another project sadly be approved that I think all of us know has very little chance of being built.”

NDP Leader Tom Mulcair accused the prime minister of hiding the approval of the Trans Mountain project behind the rejection of the much maligned Northern Gateway project.

“What Mr. Trudeau is trying to do is use Northern Gateway as cover, as camouflage, for the announcement on Kinder Morgan, which breaks a fundamental solemn promise he made to British Columbians. That’s what this is about,” Mulcair said outside the House of Commons on Tuesday.

Mulcair added that he is “very concerned” about the direction Canada’s environmental policy is headed.

“There’s no plan in Canada to reduce greenhouse gases, and there’s no possible way to reduce our overall greenhouse gas productions, because Mr. Trudeau still hasn’t done the hard work of coming up with a plan.”

Alberta Premier Rachel Notley cast a sunnier outlook on the announcement. She said that after “a long dark night” for Alberta’s economy, the province is “finally seeing some morning light.”

“We're getting a chance to sell to China and other new markets at better prices. We're getting a chance to reduce our dependence on one market, and therefore to be more economically independent. And we're getting a chance to pick ourselves up and move forward again,” she said at a press conference in Ottawa.

Notley reiterated Alberta’s plan to eliminate coal-derived energy by 2030 and its carbon tax, both of which are seen as ways to temper environmental policy with oil production.

“To all Canadians, I say this: We don't have to choose between the environment and building the economy. Canada is going to going to be a global leader on climate change. And our country will still create jobs and greater economic equality,” she said.

Indigenous leaders echoed May’s call for action in light of the announcement.

"The struggle will simply intensify," said Grand Chief Stewart Phillip of the Union of British Columbia Chiefs. "It will become more litigious, it will become more political and the battle will continue."

Grand Chief Derek Nepinak of the Assembly of Manitoba Chiefs said the federal government will have to answer to Canada’s indigenous community.

"They're not going to exclude us the second time. They don't have consent to come through our treaty lands without us," he said.

"Now's our opportunity to send a clear message that we demand that we're listened to. The standard of consent is one of consensus amongst our people. And I don't see a day where our people will consent to destruction of the land, to destruction of the water. I just don't see it."

With files from the Canadian Press