Ontario drivers could soon see government-mandated stickers about the price of the carbon tax on gas pumps across the province, as the Progressive Conservatives open a new front in their battle with Ottawa over the levy.

The environment and energy ministers made the announcement Monday in one of the near-daily events the Ontario government has held to slam the tax since it was imposed one week ago.

"We will make sure that we use every tool at our disposal to make sure that Ontarians understand the impacts of this carbon tax — the impact on their business, the impacts on their families and the impact on our province's competitiveness," Environment Minister Rod Phillips said at a gas station in Oakville, Ont.

Ontario will introduce legislation that would require stickers to be put on gas pumps showing that the tax has added 4.4 cents a litre to the price of gasoline and that will rise to 11 cents per litre by 2022.

Energy Minister Greg Rickford framed it as a transparency measure.

Ontario will introduce legislation that would require stickers to be put on gas pumps showing that the tax has added 4.4 cents a litre to the price of gasoline and that will rise to 11 cents per litre by 2022. (Supplied)

"The people of Ontario deserve to know the full truth about how the federal carbon tax will make their lives more unaffordable," he said. "It will hit our wallets hardest when it comes to gas prices and home heating costs and the businesses and programs and services that we use."

Cost of stickers not disclosed

Rickford couldn't provide a cost for the move, but said it will be "very minimal."

Green party Leader Mike Schreiner called it a "scare tactic" in Premier Doug Ford's campaign to "sabotage" climate solutions.

"I'm appalled at the amount of time, resources and money being wasted on Ford's anti-climate campaign," he said in a statement. "If the government truly cared about transparency, they would putstickers at the pumps that outlined the costs of the climate emergency that we face."

The government has also asked the Ontario Energy Board to clearly reflect the cost of the carbon tax on natural gas bills. It will add about four cents to a cubic metre of natural gas.

Ontario is one of four provinces, including Manitoba, Saskatchewan and New Brunswick, where Ottawa imposed the levy because they opted not to impose their own pricing schemes on carbon emissions.

Ontario is challenging the carbon tax in court next week.

Rebates starting at $128 annually

The tax is expected to cost a typical household $258 this year and $648 by 2022. Residents of provinces with the tax will be getting rebates on their income tax returns that start at $128 annually and increase for people with spouses or dependents at home.

The federal government says a family of four in Ontario would get $307 this year.

While Ford has said he is staying out of the upcoming federal election, he has taken pains to brand the carbon pricing scheme as the "Trudeau Liberal carbon tax" and cast doubt on the rebates.

Federal Environment Minister Catherine McKenna has said putting a price on pollution and providing a rebate to consumers is a "small c conservative approach" to addressing climate change that gives consumers a choice to invest in ways to curb their energy use or pay more to maintain the status quo.

In a statement Monday, McKenna said, "It's clear that Doug Ford cares more about wasting taxpayers' dollars on misleading stickers, than on helping Ontarians save money and energy, or on coming up with a meaningful climate plan."News of the stickers comes the week after scientists "made it clear Canada is warming at double the global rate," the statement said.

"It's been 344 days since Mr. Scheer said he'd release his climate change plan and Canadians are still waiting. While Conservative politicians continue to ignore the experts and stick their heads in the sand on climate change, our Government will continue to step up and take meaningful action."

The federal tax is $20 a tonne for this year and is set to increase by $10 annually until it reaches $50 a tonne in April 2022.