"MLA for Skeena-Bulkley Valley Nathan Cullen said that "[Prime Minister Justin] Trudeau just dropped $4.5 billion of your money on a 65 year old pipeline that leaks".
Canada will also offer federal loan guarantees to ensure construction continues through the 2018 season as part of the deal with the company.
Until then, Kinder Morgan has stopped all non-essential spending on the pipeline expansion project that will triple the flow of diluted bitumen from Edmonton to Vancouver.
Meanwhile, Green Party Leader Elizabeth May pleaded guilty to criminal contempt after she protested at the Kinder Morgan construction site, violating a B.C. court injunction.
Kinder Morgan Canada's pipeline business earned $63.6 million before depreciation and amortization in the three months to the end of March, compared to earnings of $53.6 million for its terminal business.
In 2016, the Federal Court of Appeal overturned approval of the Northern Gateway pipeline project, but it was Ottawa that ultimately rejected the project.
To help attract a future buyer for the pipeline, Morneau said, the government plans to "extend the federal indemnity to protect any new owner from costs associated with politically motivated delays".
The report said a lack of investment in the energy sector is a contributing factor.
Long after getting federal approval to nearly triple the capacity of its six-decade old conduit in 2016, Kinder became the latest pipeline operator to come against fierce local opposition in Canada.
If Canada indeed ends up buying the pipeline, it will be exclusively to ensure its capacity can be tripled, allowing Canada to find new export markets for its oil resources, Morneau said - and that ultimately, the long-term goal will be to find a private-sector buyer to take it over.
Alberta has also agreed to provide funding for any unexpected costs that arise during construction.More news: Savage Lines From Drake and Pusha T's Current Diss Track War
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A new Crown corporation will manage the project.
But British Columbia's social democratic government recently joined environmental activists' fight against the pipeline, provoking a trade row with Alberta and leading Kinder Morgan to temporarily halt its construction until the dispute was resolved.
"I said to the Prime Minister that ownership of the project doesn't change my concerns", said B.C. Premier John Horgan.
In the wake of the federal government's decision to buy the Trans Mountain pipeline from Kinder Morgan, industry analysts and climate groups agree on at least one thing: The political battle over the expansion of the contentious pipeline is not over.
The government was immediately slammed from all sides for its stunning move.
Opponents say they are going to ramp up efforts to stop the pipeline from being built.
"This is the moment in history where Justin Trudeau has revealed that he never cared about Indigenous rights or reconciliation". "They want to see this pipeline completed".
Ottawa is pressing ahead, firmly of the opinion there is no doubt about its jurisdiction.
What's more, a poll in April found that a growing number and a majority of British Columbians actually support the pipeline project. "The only (way) in our estimation that that can be done is through exerting our jurisdiction by purchasing the project".
Tzeporah Berman with Stand Earth is asking people to make a pledge and stand with Indigenous First Nations.
Currently, 99 percent of Canada's oil is sold to the United States at a discount, and access to the Pacific coast is seen as key to diversifying the world's sixth-largest oil producer's energy exports.