Clark stepped out of meetings at the Council of the Federation in Halifax to make the announcement as premiers tried to cobble together a pan-Canadian strategy on energy and before they broke for their final news conference.
She said she wouldn't endorse a deal before discussions take place with Ottawa and Alberta over how B.C. would be compensated for allowing the $6-billion pipeline to carry heavy oil to the B.C. coast to be loaded onto tankers bound for Asia.
"British Columbia will not be participating in any of those discussions until after we've seen some progress that our requirements for the shipment of heavy oil will be met," she told a hastily called news conference.
"It's not a national energy strategy if British Columbia hasn't signed on."
Clark and Alberta Premier Alison Redford have been locked in an intractable dispute over economic benefits associated with the megaproject proposed by Enbridge (TSX:ENB), with Clark saying the sides must talk before there can be any movement.
She said the two had a "very frank discussion" about it Friday morning, but didn't reveal details or if they planned on holding further talks on the matter.
Redford has said she sees no point in talking since the pipeline project is a private venture and British Columbia has to decide on its own how to proceed with trying to secure more revenue from it.
At the closing news conference, Redford said the lack of unanimity on a national energy plan wasn't something that concerned her.
"I don't think we should lament the fact that we're not all the way there yet," Redford said.
"I think we should actually celebrate a tremendous amount of success in that we had almost every premier in the country talking about the fact that we need to come together and talk about how to grow Canada's energy economy."
But after much talk going into the meeting of co-operation and the evolution of a pan-Canadian energy strategy, the premiers appeared to leave with little more than the creation of a working group of premiers that will build on a 2007 plan.
Still, the host of the annual meeting, Nova Scotia Premier Darrell Dexter, said he wasn't disappointed in the results of the gathering, which addressed health care, transfer payments, changes to employment insurance and aboriginal issues. He said the work of the council can continue despite the tussle between Alberta and B.C.
"I would like to see that work that we're doing as a bridge over any kind of division," he said.
Clark has said she decided to ask for an unspecified share of benefits from the Northern Gateway after doing analysis on the development, which will move bitumen from Alberta to the B.C. coast for shipment to Asia.
Her government has released five conditions she says need to be met before she can move forward with the pipeline. In addition to the demand for a greater portion of the economic benefits, they include the completion of an environmental review now underway, assurances that the "best" responses will be available for potential spills on land and at sea, and that aboriginal rights will be recognized.
Clark repeated her position that the province bears too much risk from oil spills at sea or on land, while receiving only eight per cent in tax benefits.
She added another wrinkle to the feud when she called on Ottawa on Wednesday to sit down with her and Redford to hash out the issue. Foreign Affairs Minister John Baird responded bluntly by questioning Clark's stance and reiterating the federal government's support for the project.
Redford has flatly dismissed Clark's position as one that would "fundamentally change Confederation" because it would mean new negotiations for projects throughout the country.
According to research in an application filed by Enbridge, 8.2 per cent of the Northern Gateway's projected $81 billion tax revenue would flow to B.C. over a 30-year period. That equates to $6.7 billion for B.C., while Ottawa is expected to receive $36 billion and Alberta would earn $32 billion.
Saskatchewan is expected to top the remainder of the provinces in terms of tax benefit, receiving about $4 billion.
Enbridge's proposed 1,177-kilometre twin line would carry heavy oil from Alberta across a vast swath of pristine B.C. wilderness and First Nations territory to a port at Kitimat, B.C., for shipment to Asia.
Last week, the company announced it will shore up $500 million in safety improvements.
Next year's Council of the Federation meeting will be held in Niagara-on-the-Lake, Ont.
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