Vancouver's mayor sat down with Prime Minister Justin Trudeau in Paris today to discuss the importance of collaboration between the federal government and Canada's municipalities in fighting climate change.

Gregor Robertson met with Trudeau and Environment Minister Catherine McKenna in advance of the United Nations Climate Change Conference, which kicks off tomorrow.

While Canada isn't expected to announce any firm emissions-reduction goals during the global gathering, Robertson says he'd like to see the same ambitious emissions targets in his city adopted across the country.

Vancouver aims to become fully reliant on renewable energy by 2050, coupled with an 80 per cent reduction in greenhouse-gas emissions.

Speaking from Paris, Robertson says Canada has the opportunity to become a world leader on climate change and the green economy, which he describes as the biggest economic opportunity in the country's history.

Meanwhile, thousands of people are expected to turn up to march in global climate demonstrations in cities across Canada.