Montreal Mayor Gerald Tremblay is hoping for an extra two-cent gas tax in the next provincial budget, and increasing that by 12 cents by 2020.

Cities, including Montreal, say they would use the money to improve public transit.

Tremblay says it makes sense rather than tolls because it would be easier to implement.

"We're doing that, because if we're very serious about climate change… we have to do something," said Tremblay.

Quebec Premier Jean Charest discussed that idea at the Copenhagen summit on climate change.