Both Barack Obama and Hillary Clinton have expressed their intention to withdraw from the North American Free Trade Agreement on becoming U.S. president unless the deal is renegotiated.
The comments came during Tuesday's debate in Cleveland, Ohio between the two Democrats vying for their party's nomination -- one week before the crucial primaries in Ohio and Texas.
Each candidate was quite specific about using the six month opt-out clause in NAFTA, to pressure Canada and Mexico into renegotiating the deal.
"I have (a) very specific plan and it does include telling Canada and Mexico that we will opt out unless we renegotiate the core labour and environmental standards," Clinton said.
Obama followed Clinton's lead -- a rare area of agreement between the pair during the debate.
"I will make sure that we renegotiate in the same way that Senator Clinton talked about," he said. "I think . . . Senator Clinton's answer on this one is right. I think we should use the hammer of a potential opt-out as leverage."
NAFTA is seen as wildly unpopular with blue collar workers in the U.S., whose votes are vitally important in a state like Ohio.
The Conservative government's public reaction was muted Wednesday morning.
Canadian Finance Minister Jim Flaherty told Canada AM Wednesday morning that he "was not going to get involved in their politics."
But he did suggest that he would prefer they left NAFTA alone.
"(They) should recognize that NAFTA benefits the U.S. tremendously," Flaherty said.
'Those who speak of it as helpful to (just the) Canadian or Mexican economies are missing the point."
The Liberals were a bit more blunt.
"It would be a disaster for Canada," Liberal MP and finance critic John McCallum said on Canada AM.
But he added that, "I hope and I believe that it's politics, because they're in a high-stakes contest. I believe after this nominee is decided, this issue will go away."
Both Obama and Clinton have been critical of the long-standing trade agreement over the course of the Democratic primaries, saying that the deal has cost U.S. workers' jobs.
The March 4 primaries are seen as vital for each candidate, but particularly Clinton. It is expected that without a decisive win in both Texas and Ohio, she has no chance of winning the Democratic nomination.
Clinton once had a large lead in each state, but recent polls are showing the candidates as close to even, with Obama surging ahead.
Early polls show that there is a strong possibility of a Democrat in the White House in January 2009.
Obama, in particular, is surging in popularity throughout the U.S. and some polls give the Illinois senator an almost double-digit lead if he were to run head-to-head against the expected Republican candidate, John McCain.