Canada has been "tough" with the renegotiation of the North American Free Trade Agreement as the third round of talks beckons.

Former interim Conservative Party leader Rona Ambrose told BNN that Canada is holding its ground in the talks, but that all parties should be prepared for a rough road ahead.

“What is coming out of the talks is that Canada has been tough,” Ambrose, a member of the NAFTA advisory council said after a briefing on the second round of negotiations. “I think that’s good. We need to be tough. We need to stand our ground, particularly with all the chaos happening around President Trump’s political agenda.”

“Canada is trying – frankly, I think – to come to the table and make sure that we not only try to modernize the agreement, but do the least amount of harm possible,” she said.

However, Ambrose added that three issues central to Canadians in any new agreement remain contentious: Rules of origin, supply management and the Chapter 19 dispute resolution mechanism.

She said that Trump’s ‘America First’ approach to rules of origin remains a “detriment” to the North American supply chain. Ambrose also called Trump’s resistance to Canada’s supply management system is “uncompetitive and unfair.”

“I think we should be prepared that things will get a little messier in the next round.”

Still, Ambrose believes there’s impetus on all three nations to get a deal done in short order, particularly with a Mexican election – scheduled for July 1, 2018 – that could see the “more liberalized” Enrique Pena Nieto replaced by the more “Anti-Trump” Andres Manuel Lopez Obrador.

“I think everyone recognizes that from a practical point of view, but it really is in the best interests of North America – from an energy security point of view, from an economic union point of view, from a free trade point of view - to get this done quickly, particularly before the Mexican election.”