"Take a minute to explain to people your position and then we'll get back to this," Trudeau said during a Q&A about his memoir, Common Ground, at the Toronto Reference Library.
In a video from the event, two protesters carrying a sign about the proposed Energy East pipeline (what the sign says is obscured by the crowd) move to the front of the room, with a security guard standing nearby. It isn't clear from the video whether there were more protesters in attendance.
"Canada will fail every climate target if it goes through," one protester says of the pipeline, which would run from Alberta to New Brunswick. "As a young person, I want you, Mr. Trudeau, to call for a full climate review of Energy East."
After the man's brief speech, Trudeau urges the crowd to give the protesters a round of applause, which they do.
The protesters may have a sympathetic ear in Trudeau. In 2013, he told CBC News the proposed west-east pipeline project will not go forward unless it addresses key environmental concerns.
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