Prime Minister Justin Trudeau gave Canada’s controversial Trans Mountain pipeline expansion a second lease on life Tuesday, framing the decision in starkly political terms that portrayed his Liberal government as best positioned to walk the narrow tightrope between economic development and environmental protection.

“The truth is, it doesn’t make economic or environmental sense to sell any resource at a discount,” he told a news conference in Ottawa, a reference to the fact that Canadian energy doesn’t command a premium on the world market, since the neighbouring U.S. is the primary consumer.

“Instead, we should take advantage of what we have, and invest the profits in what comes next _ building the clean energy future that is already at our doorstep. Fundamentally, this isn’t a choice between producing more conventional energy or less. It’s a choice about where we can sell it and how we get it there safely.”

The decision to reapprove the project comes nine months after the Federal Court of Appeal ripped up the original federal approval, citing incomplete Indigenous consultations and a faulty environmental review. Trudeau says the court said the government needed to better.

“And you know what?” Trudeau said. “They were right.”

The Liberals ordered the National Energy Board to look at marine shipping impacts; Natural Resources Minister Amarjeet Sohi started another round of consultations with Indigenous communities affected by the project.

Tuesday’s decision also comes the day after the Liberals passed a motion in the House of Commons declaring climate change a national emergency that would require more cuts to emissions than have already been promised.

In 2016, the National Energy Board said the production of another 590,000 barrels of oil, which would maximize the twinned pipeline’s capacity, could generate 14-17 million more tonnes of greenhouse gases each year, which means Canada would have to find ways to cut more from other sectors to meet and then exceed its current targets.

RELATED: Trans Mountain timeline: A look at key dates in the project’s history

Trudeau says he is sympathetic to concerns about the environment and the need to transition to cleaner sources of energy, but says that in order to fund that transition, Canada needs to take advantage of its natural resources while they are still needed.

“The policies of the last century will not serve Canadians in this one,” he said, acknowledging the concerns of environmentalists who fear the twinning project will exponentially increase the risk of a catastrophic spill on the West Coast.

“I understand your desire to protect your coastline and your ocean, because I share it,” he said directly to British Columbia residents. “Our top priority is making sure there is no spill in the first place, but we know we need to be prepared for anything.”

Before he was done, however, Trudeau struck a decidedly partisan note.

“The Conservatives built exactly zero pipelines to new markets, but they did manage to build one thing: extreme animosity between those who want pipelines and those who don’t,” he said. “Conservatives are fine with dividing Canadians and pitting provinces against each other, but we’re focused on getting the best result for all Canadians.”

The government will require that every dollar in federal revenue coming from the project be reinvested in clean energy and green technology. That includes an estimated $500 million a year in new annual corporate tax revenues once the pipeline is in service, as well as any revenues from the promised sale of the entire expanded pipeline back to the private sector.

The Prime Minister is vowing that every dollar of profit earned through the pipeline expansion will be invested in green energy and technologies. When the expansion is fully operational those profits are estimated at $500-million annually #cdnpoli — Cormac Mac Sweeney (@cmaconthehill) June 18, 2019

“To those who want sustainable energy and a cleaner environment, know that I want that too,” said Trudeau. “But in order to bridge the gap between where we are and where we’re going, we need money to pay for it.”

Trudeau says construction will restart this construction season, but there is no specific date yet. Trans Mountain Canada will have to apply a second time for all the necessary federal, provincial and municipal permits before breaking ground.

Photo credit: Kinder Morgan/CP

The federal cabinet is also requiring another consultation with Indigenous communities affected by the project to determine how they can potentially become economic partners in the project.

The government has accepted the 156 conditions the National Energy Board put on the project approval, but is amending six of them to include requiring Indigenous communities to be involved in developing marine emergency response plans, mitigating potential impacts on sacred sites, and Indigenous involvement in post-construction environmental impact reporting.

There are also eight new accommodations required to take into account Indigenous concerns, including working with some communities to potentially move the route.

Timeline: A look at key dates in Trans Mountain’s history