REGINA -- The premiers of Alberta and Saskatchewan say Energy East would have been a nation-building project and that TransCanada's decision to cancel the pipeline is a bad day for the West.

Alberta Premier Rachel Notley says Energy East -- which would have carried Alberta oil to tidewater -- would have benefited all of Canada with new jobs, investment, energy security and the ability to displace imported oil.

Saskatchewan Premier Brad Wall says the reasons for the decision fall at the feet of Prime Minister Justin Trudeau and the federal government.

Wall says they've been "at best, ambivalent about the project" and then changed the rules for the regulator review at the last moment.

He says the expectation from the federal government, and some powerful central Canadian interests, is that the West "will just grin and bear this latest blow" to its economy and people.

Calgary-based TransCanada said it's abandoning the project after a careful review of changed circumstances.

"We have a company that committed more than a billion dollars to a project and made earnest efforts to address the concerns of the public and regulators. A company that made 700 changes to its plans as part of that response," Wall said in a statement Thursday.

"Make no mistake, other companies' decisions to invest in Canada will be informed by this debacle."

Supporters say Energy East was necessary to expand Alberta's markets and decrease its dependency on shipments to the United States. Detractors raised questions about the potential environmental impact.

"We are deeply disappointed by the recent decision from TransCanada," Notley said in a statement. "We understand that it is driven by a broad range of factors that any responsible business must consider. Nonetheless, this is an unfortunate outcome for Canadians."

Notley suggested more clarity is needed going forward.

"The National Energy Board needs to send a clear message on what the future of project reviews look like in Canada," she said.

"Our government understands that deliberation on upstream emissions and land-use integrity is important and must continue. Investors need confidence and we look forward to seeing that certainty in place soon."