The Montreal MP would do away with the current requirement that post-secondary students begin paying off their student loans six months after graduation, whether or not they've found a job.
He would give them an indefinite grace period, requiring graduates to start repaying loans only after they've found a good-paying job of about $40,000 per year.
Garneau, who is touting himself as the most substantive of nine leadership contenders, is to unveil his latest policy proposal Monday.
An engineer and former astronaut with impressive academic credentials, he has made building a more diversified "knowledge economy" one of the cornerstones of his campaign.
He maintains that giving young people more opportunity to succeed is key to Canada's future economic competitiveness.
His campaign says the latest proposal is aimed at alleviating the "double whammy" facing young Canadians, who often find it hard to find a good job after graduating with staggering debts that they must begin paying off almost immediately.
At 15 per cent, the rate of youth unemployment is almost double the national average.
Garneau has already proposed eliminating payroll taxes for employers who hire young workers.
Since education is a provincial jurisdiction, Garneau would allow provinces to opt out of his proposal to extend the grace period for repaying student loans.
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