As the Ontario government vows to continue its fight against the federal carbon tax, Green Party of Ontario Leader Mike Schreiner says the money being used in that fight could go to better things.

"It's reckless and it's wrong for the premier to be wasting our money, our tax dollars, sabotaging climate solutions," the Guelph MPP said Monday afternoon.

Environment Minister Rod Phillips vowed on Monday, as the federal carbon tax took effect in the province, that the government "will use every tool at our disposal to challenge" it.

The federal government imposed a carbon tax on greenhouse gas-emitting fuels in four provinces that have refused to take part in their plan: Ontario, Saskatchewan, Manitoba and New Brunswick.

"We don't need a carbon tax to fight climate change," Phillips said.

But Schreiner says a legal fight will cost $30 million and there's talk the Ontario government will be rolling out advertising against the carbon tax.

"It's just wrong," he said.

"Instead of spending the money on ad campaigns and lawyers, why don't we spend it on the people of Ontario," he said.

Schriener suggested the money could instead be used to help people make the shift to electric vehicles, retrofit their homes so they can save money by saving energy, invest in public transit and support companies that are investing in a clean economy.

"That would offer true economic benefits and help us fight climate change," he said.

He also questioned tweets on Sunday where "every member of the PC caucus was out filling their cars up with gas."

"I can fill my car up with electricity and operate it at one-fifth the cost of a fossil-fueled powered vehicle," Schreiner said.

Last chance to fill up before for the Justin Trudeau <a href="https://twitter.com/hashtag/CarbonTax?src=hash&ref_src=twsrc%5Etfw">#CarbonTax</a> kicks in tomorrow. Starting April 1st, gas will go up almost 4.5¢ /L, which will grow to 11¢ /L by 2022. <a href="https://twitter.com/hashtag/onpoli?src=hash&ref_src=twsrc%5Etfw">#onpoli</a> <a href="https://t.co/ueohGGPfWB">pic.twitter.com/ueohGGPfWB</a> —@mikeharrisjrpc

Today is the last day to fill up before the Federal Carbon Tax comes to Ontario.<br><br>Fill up today ... tomorrow the Federal government is charging you more with a Carbon Tax that will result in a ¢4.4/litre increase to the price of gas. <a href="https://t.co/kEiU1dc7Xk">pic.twitter.com/kEiU1dc7Xk</a> —@VictorFedeli

It’s so cold in Ottawa today that Justin Trudeau has his hands in his own pockets. That changes tomorrow though when the weather warms up and his carbon tax kicks in at the pumps. <a href="https://twitter.com/hashtag/itssnowinginottawa?src=hash&ref_src=twsrc%5Etfw">#itssnowinginottawa</a> <a href="https://t.co/o4J5XMUXMJ">pic.twitter.com/o4J5XMUXMJ</a> —@MacLeodLisa

Environment Minister Catherine McKenna also defended the carbon tax on Monday in an interview on CBC Toronto's Metro Morning.

"Pollution doesn't know any borders so you need to make sure you have a plan across the country," she said.