Ontario NDP Leader Andrea Horwath says it’s time for Premier Doug Ford to “back away” from his carbon tax court challenge, now that voters have given Prime Minister Justin Trudeau a fresh mandate on fighting climate change.

“What the election showed is that there are many people from coast-to-coast to coast around this country who are concerned about climate change,” Horwath told reporters Wednesday.

“Here we have Mr. Ford still fighting against the environment. He needs to back away from that, drop that wasted energy and time.”

Ford’s Progressive Conservatives promised during the 2018 federal election campaign to spend $30 million to fight the federal government’s price on carbon emissions and mounted a court challenge soon after taking office.

In June, the Ontario Court of Appeal ruled against the Ford government arguing that tackling climate change is a federal responsibility and that the government is imposing a regulatory charge, not a tax on emitters – a decision that Ontario is appealing to the Supreme Court.

While Ford suggested in August that the outcome of the federal election campaign would determine his government’s next steps, a spokesperson for the premier’s office says the provincial Tories have yet to arrive at a decision.

“As we evaluate the results of the federal election, and as the premier said previously, we will continue to discuss our government’s efforts to fight the federal carbon tax,” Kayla Iafelice, spokesperson for the premier, said.

During a fireside chat with the C.D. Howe institute, Wednesday, Ford restated his disdain for the carbon tax but did not discuss the court challenge.

“[The tax] in my opinion, is the worst tax you could ever face. It makes things unaffordable,” Ford told a business crowd. The media was not invited to attend the event and was unable to ask Ford about whether his thinking has changed as a result of the federal election.

Horwath, however, is cautioning the premier against pressing ahead with the legal battle because climate change was “one of the big issues that was central to the campaign.”

“You don’t start a new relationship with a newly elected government by bringing back your court challenge on carbon taxes,” Horwath said.

“That’s not a good first step.”