"I can categorically say that no one has contacted our embassy or our ambassador," said Canadian Foreign Ministry spokesman Andre Lemay. "None of our officials at the embassy discussed anything with the runners up in the presidential campaign. We realize that one of the Canadian networks mentioned yesterday that such a call had been made. The report is untrue."
When asked whether Ambassador Michael Wilson, the Canadian emissary to the U.S., had received a call from anyone in the Obama campaign, Lemay said he had not.
Wilson "was not contacted by anybody," said Lemay. "Nor was any official in our embassy."
"We are saying the story is untrue," Lemay reiterated.
CTV, the Canadian television network, reported Wednesday night that a "senior member" of the Obama campaign called Wilson "within the last month" to warn him that Obama would "take some heavy swings" at NAFTA as part of his campaign.
The Obama insider, according to CTV, told the ambassador, "Don't worry - it's just campaign rhetoric, it's not serious," CTV reported.
CTV reported that the Obama campaign's message to Wilson was taken as "completely authentic" by the Canadian government.
At Tuesday's debate in Cleveland, Sen. Hillary Clinton said that as president she would opt out of the North American Free Trade Agreement in six months, if she couldn't renegotiate the agreement with Canada and Mexico to her satisfaction.
"I will make sure we renegotiate," Obama agreed. "I think we should use the hammer of a potential opt-out as leverage to ensure that we actually get labor and environmental standards that are enforced."
Democrats count labor unions among their biggest supporters, and labor unions blame NAFTA for eliminating jobs.
On Wednesday, Canada's Trade Minister David Emerson said NAFTA is at risk, given Clinton and Obama's threats to end it, the Bloomberg News Service reported.
"The rhetoric of protectionism has been creeping up and getting more strident," Emerson was quoted as saying. "It's not just the heat of the presidential campaign," there's a grassroots movement against it as well, he said.
Emerson said Mexico, Canada and the United States all benefit from the 1994 trade deal, which was negotiated by the Clinton administration. "The dismantling of trade barriers and the opening of markets has led to economic growth and rising prosperity in all three countries," the U.S. Commerce Department says on its Web site.
Canada is the USA's biggest trading partner.
Bloomberg also quoted Finance Minister Jim Flaherty as saying that it will be "very important" for the eventual U.S. presidential nominee to talk with "those who are very knowledgeable about" NAFTA.
Obama has not directly responded to questions about his differing private and public stands on NAFTA. A spokesperson for the Obama campaign told CTV that the Obama staffer's conversation with Ambassador Wilson sounded implausible, but the spokesperson did not deny that the Obama campaign had contacted Wilson.
"Senator Obama does not make promises he doesn't intend to keep," the spokesperson told CTV.