TransCanada made the announcement Thursday.
"Our government has approved two major export pipelines that are now under construction, and a third is expected to start soon".
Energy producers in Alberta had hoped the TransCanada projects would help them diversify their markets, with most of the existing pipeline network linking the energy-rich province to the U.S. Midwest and Gulf Coast.
As Energy East supporters lamented the loss of jobs and revenue, Indigenous opponents, environmental activists and a number of Quebec politicians celebrated.
The decision comes after Canada's national energy regulator expanded its review of the projects in August.
Saskatchewan Premier Brad Wall was an advocate for the pipeline project, voicing his support for it on many occasions, including trips to eastern Canada.
Watch below: Natural Resource Minister Jim Carr says the TransCanada decision to cancel the Energy East pipeline was not motivated by government policies, but rather changes in the markets and commodity prices.
The vast majority of Canadian crude exports go to the United States, and Energy East would have shipped 1.1 million barrels a day to east coast ports for loading onto tankers destined for higher-priced markets in Europe and Asia.
The Liberals are defending jobs while protecting the environment, Trudeau insisted during question period, but "the market conditions have changed fundamentally" since the pipeline was proposed, including a steep drop in oil prices, he said.
The pipeline's importance has somewhat diminished for TransCanada since the United States this year approved Keystone XL pipeline, which would run from Alberta to US refineries, but supporters said they were "extremely disappointed" by the decision.
Citing "changed circumstances" company President Russ Girling says they will be informing the National Energy Board of their plans to cancel the project.
Supporters said the pipeline was necessary to decrease reliance on the US, which takes 97 percent of Canada's energy exports.
He said that companies like TransCanada and Petronas have opportunities to invest in other jurisdictions and, for both companies, investment elsewhere looked more attractive given the constant changes to Canada's regulatory structure.
"I think the federal government has erred there and I think it's incumbent on the Trudeau government to come clean on what they want the NEB to do so that we don't make this mistake in the future as well", Nenshi said.
"As far as we're concerned, the whole criteria around social acceptability of major projects has become more and more important in terms of how we evaluate projects like Energy East and others".
TransCanada said last month that it would halt its efforts to get regulatory approvals for the controversial projects.
"This project was so wrong and so risky, its hard to believe it was seriously contemplated", Gretchen Fitzgerald, national program director of environmental organization the Sierra Club, said.