Tobin is one of more than three dozen business leaders, along with current and former politicians featured in a full-page newspaper ad that ran nationwide Thursday, extolling support for the project.
"These projects are possible. They're not easy," said Tobin, who was at the helm of the easternmost province when government finalized agreements for the Hibernia, Terra Nova and White Rose offshore oil installations.
"If we can find ways to meet and respond to everybody's concerns, they are profoundly important to future prosperity both within regions of Canada and for the country as a whole."
Tobin, who is also a former Liberal member of Parliament, was discreet about Liberal Leader Justin Trudeau's opposition to the project.
"I'm not a cheerleader for Enbridge in the sense of saying let's do it no matter what," said Tobin, now vice-chairman of BMO Financial Group.
"I'm saying let's see if we can work together and rise to the challenge and make this thing happen in an environmentally safe way, in a manner that shares the benefits across British Columbia, Alberta and, in particular, makes equity participants — ownership participants — of First Nations communities."
The open letter published in the Globe and Mail, the Ottawa Citizen, and daily newspapers in British Columbia was also signed by former Liberal deputy prime minister John Manley — now the president of the Canadian Council of Chief Executives.
Other signatories include former Conservative cabinet ministers, such as Perrin Beatty and Chuck Strahl, as well as Alberta Premier Dave Hancock and Saskatchewan Premier Brad Wall.
"... Projects of national significance can become the catalyst for new and better standards for these important industries," the ad said.
"As signatories to this letter, we strongly believe that Northern Gateway is a project that's right for our time."
The federal cabinet has until next Tuesday to announce the final decision on the Northern Gateway project.
Tobin said he anticipates the project will be approved, along with 209 conditions already recommended by the federal review panel.
B.C. NDP Leader John Horgan said the provincial government — which officially opposed the project at review hearings — should listen to British Columbians and not eastern politicians.
"Northern British Columbians and First Nations don't care which former Ontario premier or Goldman Sachs executive is in favour of this project," Horgan said.
"Eastern politicians and investment bankers aren't being asked to put their environment, community and economy at risk with next-to-no benefit."
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