Natural Resources Minister Jim Carr says his comments about the possible use of "defence forces" or police during future protests over pipeline projects approved this week by Ottawa weren't meant to be read as a threat.

"There is no warning intended," Carr told CBC Radio's The House in an interview to air Saturday.

Carr spoke on Thursday to business leaders in Edmonton, where he heard from pipeline companies and contractors worried over the safety of their workers in face of potentially violent protests.

Opponents to Kinder Morgan's Trans Mountain project, which would expand an existing pipeline carrying diluted oilsands bitumen from Alberta to a terminal near Vancouver, have vowed to delay or kill it by any means possible.

"If people choose for their own reasons not to be peaceful, then the government of Canada, through its defence forces, through its police forces, will ensure that people will be kept safe," Carr told the crowd.

"If people determine for their own reasons that that's not the path they want to follow, then we live under the rule of law."

In an interview earlier Friday with CBC Radio's The House, Carr said he wasn't suggesting the government would bring in the army to face off with protesters.

"I mean to say that, if you look at all of my comments, that we celebrate and cherish our capacity in this free society to be be able to protest," he said.

"People will protest in peaceful ways and that's not only acceptable it's a hallmark of who we are as Canadians."

'No such authority'

During Friday's question period in the House of Commons, New Democrat Randall Garrison condemned Carr's "reckless, irresponsible and incendiary language" in suggesting the federal government would use police and defence forces to counter protests against the Kinder Morgen pipeline, only two days after the project was approved.

"If he's truly concerned about the rule of law, he should know that in this country the federal government has no such authority to use our military against pipeline protests," Garrison said.

Responding on behalf of Defence Minister Harjit Sajjan, Transport Minister Marc Garneau said the right to protest peacefully is one of the cornerstones of Canadian democracy.

"We will always protect the right of Canadians to protest when they don't agree with something. They have the right to do it, they feel strongly about it, and we know and we're confident that they will do so peacefully," he said.

A small group of protesters turned up at Prime Minister Justin Trudeau's speech Friday to an elementary teachers union in Toronto. (CBC News)

Protesters at Prime Minister Justin Trudeau's speaking engagement at an elementary teachers union event in Toronto Friday held up banners that included one saying, "No more pipelines."

Trudeau acknowledged their message, but said he refuses to make a choice between what's good for the environment and what's good for the economy.

I know there's lots of people who disagree with me on this decision, and that's fine and that's fair and you're allowed to. - Prime Minister Justin Trudeau

"Adding a pipeline is consistent with reaching our climate targets. And the reason why, even though that's counter-intuitive, is that Alberta has put an absolute cap of 100 mega-tonnes emissions that they will not go over," he said. "There is growth to be had in the oilsands. They will be developing more fossil fuels while there's a market for it, while we transition off fossil fuels.

"So the question is: How do we want those fuels carried to markets? Do we want it to go through rail, which as we know is more expensive, more emitting and much more dangerous — both for communities, for the environment and for individuals — or do we want to do it the safe, modern way?" he said.

"I know there's lots of people who disagree with me on this decision, and that's fine, and that's fair and you're allowed to. Governing is about making difficult decisions," he said. "Quite frankly, that's something that I'm very comfortable with. And I look forward to working with people to manage and mitigate the very real fears that a lot of people have about what might happen."