The accord continuation, which was announced Wednesday with Quebec Premier Philippe Couillard, will run for 10 years.
Harper and Couillard say municipalities will benefit from $5 billion from the gas tax fund plus an additional $2.5 billion from the provincial government, bringing the total to $7.5 billion.
Harper also announced that the admissibility criteria for the fund will be widened.
Projects related to amateur sports and tourism will now be considered admissible along with traditional infrastructure efforts such as aqueducts, roads and water filtration.
Harper said it will be up to the municipalities to decide how they want to spend the money.
"In our past gas tax funds, we've seen literally thousands of projects across the country, whether they're community centres or local roads or sporting facilities," he said. "Various things have been and will be approved so as I say it's ultimately up to the municipalities themselves.
"We've seen great things happen because of the gas tax fund across the country, in Quebec and elsewhere, and I think that will continue going forward."
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