OTTAWA -- Former prime minister Brian Mulroney says it's possible the NAFTA renegotiation will be done in time for the 2019 federal election, but he warns Canada and the U.S. need to solve their softwood lumber woes soon or risk the long-running trade irritant derailing the broader trade talks.

Mulroney, who as prime minister from 1984 to 1993 led the efforts on both the Canada-U.S. free trade agreement and NAFTA, says Canada should prepare for a long-distance run, not a sprint, when it comes to rejigging the 23-year-old agreement.

"I think that this is not going to be short and sweet," Mulroney said in an interview with Evan Solomon, host of CTV's Question Period, which will air Sunday morning.

Still, asked if the talks would run past the 2019 federal election, Mulroney said no.

"I think we'll have it done by then," he said.

Mulroney praised Foreign Affairs Minister Chrystia Freeland and Canadian Ambassador to the U.S. David MacNaughton for their work on the decades-long softwood lumber dispute, which was reopened after a 10-year agreement -- plus a one-year extension -- expired last October. The Americans started charging up to 24 per cent tariffs on Canadian softwood in April, with the threat of more tariffs to come.

U.S. Trade Representative Robert Lighthizer has suggested he'd like to wrap up the softwood talks before plunging into the much broader NAFTA renegotiations.

Mulroney says Freeland is meeting regularly with Commerce Secretary Wilbur Ross.

"Both sides recognize that if we can, we must solve the softwood lumber case now. Otherwise it runs the risk of poisoning the larger negotiations," the former prime minister said.

When it comes to threatening retaliation, Mulroney says the Americans know Canada can retaliate with its own trade barriers, and "we don't have to say that to flex our muscles." When it comes to the challenge by Boeing to Canada's Bombardier, for example, MacNaughton told the company point blank that sparking a trade dispute like that could threaten the business relationship.

"We don't deal with somebody who on the Monday who is going to sell us billions of dollars worth of aircraft and the next day are acting to cripple a leading Canadian corporation like Bombardier," Mulroney said.

"It's not in the headlines, but I happen to know that that's the position that they've adopted and I think it's the right one."

Most important, he says, the federal government needs to keep its eye on the long game -- the NAFTA talks -- and ignore the public pronouncements coming from the Trump administration.

"We should avoid public shouting matches with the Americans as we prepare to sit down for the whole ball of wax," he said.