OTTAWA -- Conservative leadership candidate Michael Chong says Canada should impose its own tariffs to fight back against American trade measures, and threatens retaliatory action if he were to become prime minister.

"Look, we're dealing with an American president who is bullying Canadians, who is bullying our economic sectors, and we have to punch back hard," Chong told Evan Solomon, host of CTV's Question Period.

"Obviously we shouldn't throw the first punch, but if they've thrown the first punch, we should throw one back. That's the only way that we'll get their attention and make them understand that there are consequences for their actions."

U.S. President Donald Trump promised during his election campaign to renegotiate or kill NAFTA, and to pull out of the newly negotiated Trans-Pacific Partnership. He followed through almost immediately on the TPP deal, killing the 13-country agreement outright.

In the past few weeks, U.S.-Canada trade tensions have escalated: the Americans imposed a 24 per cent tariff on Canadian softwood lumber -- a dispute that has been simmering since Barack Obama was president -- while Prime Minister Justin Trudeau says he is considering banning U.S. coal exports. U.S. Commerce Secretary Wilbur Ross called the threat inappropriate.

Less than a month ago, Ross denied to CTV News that Canada and the U.S. were on the brink of a trade war.

Chong says Canada didn't start the trade war, and he would put a retaliatory tariff on thermal coal, something B.C. Premier Christy Clark has requested. He says Canada has to be clear it's willing to "play hard ball," starting with identifying American sectors where retaliatory measures would have a negative impact -- particularly in areas where Trump won the primary vote and the election.

"We support NAFTA, we support two-way trade with the United States," Chong said.

"But if they want to go down that path, we have to stand up for our interests. If we don't, if we're meek and mild about it, we will get railroaded in the renegotiation process."

British Columbia MP Peter Julian, who is running for the federal NDP leadership, says the court is the best place to win on softwood.

"What I would do [as prime minister] is what the Conservatives didn't do through the last softwood conflict, which is they basically gave up before we had passed the finish line on court actions that had been remarkably successful in American courts," Julian said in a Question Period debate with Chong.

"What the Harper government did was basically back off and sign a bad deal that led to the loss of tens of thousands of jobs, including 2,000 in my riding of Burnaby-New Westminster."

"We would have won last time if the Harper government had actually gone through that final appeal that we were bound to win, and the companies knew it and the workers knew it, and it was a real betrayal of the industry," Julian added.

British Columbians clear on pipeline

Last week, British Columbians gave the Green Party the balance of power in the province's legislature, giving them three seats while the B.C. Liberals took 43 and the NDP won 41. That's thrown into question the future of Kinder Morgan's Trans Mountain pipeline, which both the NDP and Green Party campaigned against.

Julian says B.C. voters were clear about the pipeline.

"Sixty per cent of British Columbians voted for parties that reject the Kinder Morgan pipeline for the simple reason that it puts the coast at risk, it puts the economy at risk, [and] that hurts British Columbia, but also all Canadians," he said.

"That that should be a signal to the federal government to not push through with something that's rejected by B.C."

Chong says pipelines that cross provincial boundaries are exclusively federal jurisdiction, and the federal cabinet has to stand behind its decision to green-light Trans Mountain.

"The federal cabinet has approved it based on the National Energy Board's recommendations. Communities along the route, including indigenous communities, were consulted," Chong said.

"Landlocked provinces like Alberta have the right to get their resources to market. If we don't see the construction of these pipelines, allowing landlocked provinces like Alberta to get these resources to market, we are undermining the very principles that underpin a country."