MONTREAL -- Parents with young children in tow were among those who gathered in downtown Montreal on Sunday to denounce the prospect of a fee increases to Quebec's landmark daycare program.

Quebec's Liberal government has floated the idea of introducing a sliding payment scale that could go as high as $20-a-day, based on family income level.

The daily fee currently sits at $7.30 for those who send their children to government-funded daycare centres.

One parent, Stephanie Lamoureux, says she's worried fee increases would hurt the middle class and discourage mothers with young families from going back to work.

Unions, daycare workers and representatives from Quebec's opposition parties also came out against the move.

Premier Philippe Couillard has argued a sliding-scale system would be easier on low-income families, rather than imposing an across-the-board $2 hike.

Parents initially paid $5 a day when the Parti Quebecois launched the program in the late 1990s.