Canada has an advantage over Mexico when it comes to its trade relationships with the United States, interim Conservative leader Rona Ambrose says, following meetings in Washington, D.C. last week.

Ambrose says the Canada-U.S. free trade agreement, which was the predecessor to the three-country North American Free Trade Agreement, puts Canada in a better position than Mexico.

"We don't start from scratch," Ambrose said in an interview with Evan Solomon, host of CTV's Question Period, in an interview to air Sunday morning.

"The bottom line is, even from a legal framework point of view, we have an incredibly integrated economy with the United States. It's not just NAFTA. We have a trade agreement that precedes NAFTA. We have a different situation than Mexico does with the United States. That's clear. So I think we start from a much, much better position."

Ambrose wouldn't say whether she thinks Canada should work bilaterally with the U.S. rather than including Mexico in trilateral discussions.

"I don't think at this point we know what's going to happen. The unpredictability of [U.S. President] Donald Trump leaves a lot of anxiety obviously for a lot of people," she said.

"Unlike Mexico, we do have a fairly balanced trade ratio with the United States."

Trump pledged during the presidential campaign to take the U.S. out of the 12-country Trans-Pacific Partnership and to renegotiate NAFTA or tear it up if it can't be renegotiated. He has already signed an executive order to pull the U.S. out of the TPP, essentially killing the deal.

Ambrose met with Republican congressmen and senators during her visit to Washington, and warns "there will be some tough challenges for us around trade irritants" that the Americans have raised in the past, including Canada's supply-managed dairy sector, which severely restricts foreign imports, and country-of-origin labelling on beef, pork and lamb products.

"The Americans may be our best friends, but they're also our biggest competitors. And we've had trade challenges with them in the past, and we know what they are, and I think they'll probably come after those same ones again," she said.

"These are going to be some tough discussions for us, there's no doubt about it," Ambrose said. "I do think that they will come after certain things."

The interim official opposition leader urged Prime MInister Justin Trudeau to continue talks with Japan, whether bilaterally or multilaterally, to follow on the negotiations for the TPP. The TPP was structured so that it needed American participation in order to be finalized.

"Japan is still very interested [in trade]. A lot of work has been done there. Japan is a very good economy for us to be trading with," Ambrose said, adding she prefers trade with Japan to potentially trading with China.

"We're the party of free trade. We think that we need to open up as many markets as possible for our businesses in Canada. But I do worry about the fact that there's nothing really free with China," she said.