The project was a 4,600 kilometre pipeline that would have carried up to 1.1 million barrels of crude oil a day.
"We are disappointed with this decision", said Ian Whitcomb.
Another pipeline, the Keystone XL project, which got approval from President Donald Trump in March has struggled to find interested oil producers and refiners.
In late August, the National Energy Board - an independent regulatory agency that oversees global and inter-provincial oil and gas pipelines - announced it would consider upstream and downstream greenhouse gas emissions in determining whether the Energy East pipeline was in the national interest.More news: Air France Flight Diverted After Engine Explodes
It's cancelling plans for both the Energy East pipeline and Eastern Mainline projects.
"Given increasing public interest in GHG emissions, together with increasing governmental actions and commitments (including the federal government's stated interest in assessing upstream GHG emissions associated with major pipelines), the Board is of the view that it should also consider indirect GHG emissions in its [National Energy Board] Act public interest determination for each of the Projects". The same logic that killed Energy East should help kill Keystone XL.
"This is an unfortunate outcome for Canadians", said Notley in a statement. "With the world quickly turning to renewable energy, there's no need for more outdated fossil fuel projects".
With this cancellation, there remains one more tar sands pipeline that has been proposed in Canada, taking oil to the West Coast.
The company said it was taking a non-cash charge of C$1 billion in the current quarter because of the cancellation.More news: Radhe Maa spotted on SHO's chair, officer transferred, Delhi Police begins probe
The review process is over, but several legal challenges to the pipeline - including over whether the environmental review adequately considered climate impacts - have tied the project up in the courts. The Calgary-based company refused to give further explanation.
February 3, 2016: The National Energy Board directing TransCanada to rework its application to build the contentious Energy East pipeline because the document is too hard to understand - even for experts.
Reaction across the country has been mixed.
September 9, 2016: The National Energy Board sidelines all three Energy East reviewers following complaints that two of them met privately with a TransCanada consultant the year before and discussed the proposed oil pipeline. "Nothing has changed in the government's decision-making process". "We accepted the reversal of Enbridge's Line 9B (pipeline through Montreal), but we ensured there were measures in place to follow up and protect the community".
Oil prices have roughly halved since 2014. Look at the number of transnational oil companies exiting the oil sands, selling their assets due to the high costs of extraction and production: StatOil, Conoco-Phillips, Royal Dutch Shell.More news: Harry and Barack Obama cheer on wheelchair basketball players at Invictus Games