Ontario's finance minister is warning any Canada-U.S. trade war would hurt the American economy and risk America's export market.

Charles Sousa says Ontario is a major buyer of American goods, with its auto sector intricately linked to that of the U.S.

"[The Americans] need that relationship to exist for their very manufacturing base," Sousa said in an interview with Evan Solomon, host of CTV's Question Period.

"And I believe that'll be very clear... They rely heavily on us as well."

Canada is the top export destination for 35 American states.

Canadian fears of trade trouble are ramping up as U.S. president-elect Donald Trump's Jan. 20 inauguration day approaches. Canada and the U.S. were already well down the path to a softwood lumber dispute, missing several deadlines to reach a new deal following a decade of relative peace in the sector.

Trump promised during his election campaign to throw out the 12-country Trans-Pacific Partnership agreement, of which Canada is a part, and pledged to renegotiate NAFTA or tear it up.

On Friday, the Canadian Press reported the U.S. International Trade Commission found indications the Canadian softwood lumber materially injured the American industry. That follows anti-dumping and countervailing duty investigations launched last month by the U.S. Commerce Department.

Maryscott Greenwood, senior adviser to the Canadian-American Business Council, says there's a "100 per cent chance of a trade war."

"Canada should be worried. I think it is worried," she said on CTV's Question Period.

"The silver lining, if there is one, and I hope there is one, is when Canada and the United States work together, it's a really good deal. And this president-elect is someone who really appreciates a good deal. So let's hope he looks at it that way."

"The Canadian government, the officials, the political people, [Canadian] Ambassador David MacNaughton, are incredibly shrewd, " Greenwood said.

"They know what's going on and they're getting ready."

Sousa says Canada buys from the U.S. more than it exports there.

"The president-elect will come to realize they rely heavily on the Ontario market. We buy $59 billion worth of assembled and parts manufacturing from the United States," he said.

"Hundreds of thousands of jobs in the United States are reliant on the Canadian marketplace.... Half of that trade is here in Ontario. That relationship is critical to the wellbeing of the very states that elected Donald Trump."

To watch the full interviews, tune into Question Period Sunday mornings on CTV or CTV News Channel at 11 am ET, 10 am CT, 9 am MT, 8 am PT.