As Trudeau began taking questions from two of the forum's hosts, some delegates began to heckle and jeer while several rows of young people turned to face the back of the room, prompting harsh words from the prime minister himself.
Their actions sent the wrong signal to the other young people in the room, Trudeau told his detractors.
Protesters turn their backs on Prime Minister Justin Trudeau as he addresses the Canadian Labour Congress National Young Workers' Summit in Ottawa on Oct. 25, 2016. (Photos: Fred Chartrand/CP)
"It is a little bit frustrating for me to come in, sit down, look forward to hearing from you, talking with you, and seeing a room full of people who are standing in a way that shows they're not listening," he said.
"And I think it reflects poorly on everyone who does want to listen and engage."
While Trudeau was applauded and cheered by some for defending himself, several delegates shouted back, calling the PM a "hypocrite" and holding signs reading "Keep the Promise."
Many of the delegates were upset with the Liberal government's support for the controversial Trans Pacific Partnership trade deal, as well as Finance Minister Bill Morneau's recent comments about "job churn."
"It is a little bit frustrating for me to come in, sit down, look forward to hearing from you, talking with you, and seeing a room full of people who are standing in a way that shows they're not listening."
This past weekend, Morneau told Liberal party insiders in Niagara Falls that the government needs to prepare for high turnover and short-term contracts among youth because such jobs are here to stay.
"How do we train and retrain people as they move from job to job to job? Because it's going to happen. We have to accept that," Morneau said.
The comments prompted cries of arrogance from the opposition Conservatives and New Democrats, who accused the finance minister of lacking an understanding of Canada's youth unemployment problem.
Many young people at Tuesday's forum, which was organized by the Canadian Labour Congress, voiced frustration about their employment prospects, and booed as Trudeau also suggested that precarious work _ including jobs with no pensions _ is a fact of life.
"It's simply unacceptable when the minister of finance is saying young people need to get used to precarity, young people need to get used to not having the same opportunity as other generations have had," said Briana Broderick, a youth delegate representing the United Steel Workers union at the forum.
"This concept that we won't have as much as other generations had, that's really frustrating people."
Trudeau said the issue of precarious employment is a major concern for his government, and why the Liberals pushed so hard to reach a recent agreement with the provinces to make improvements to the Canada Pension Plan.
Youth unemployment problem
The youth unemployment rate in Canada is almost twice the national average and has been since last year's election campaign, when the Liberals promised to create 125,000 jobs annually for young people by spending $1.5 billion over four years on a youth employment strategy.
Employment numbers for August showed the youth jobless rate was little changed from a year ago at 13.2 per cent.
Vass Bednar, who chairs a new federal panel on youth unemployment, has warned the country could see economic and social ripples in the future without a clearer picture about where and how young people are failing in the labour market.
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