WINNIPEG -- Manitoba Premier Brian Pallister says he won't abandon his province's lawsuit against the federal government's carbon tax, despite the fact Saskatchewan and Ontario have lost similar cases in court.

Manitoba filed its constitutional question on April 24 in Federal Court.

The province's case echoes both Ontario and Saskatchewan in arguing that it's unconstitutional for Ottawa to impose the carbon levy, which is remitted through tax rebates and green-energy programs.

It also accuses the federal Liberals of being unfair in imposing a fuel charge that's higher than what exists in other jurisdictions, and argues Ottawa did not adequately consider Pallister's now-cancelled flat-rate carbon tax.

Pallister has said the federal tax is more about politics than science, and that Manitoba's lawsuit will not cost taxpayers very much because the province will mainly use its own lawyers.

New Brunswick Premier Blaine Higgs said last week that he's considering scrapping his plan to sue Ottawa over the carbon levy, after Ontario's and Saskatchewan's cases were shot down by their top courts this spring.

"We believe we have a compelling case to make," Pallister told the Winnipeg Free Press newspaper on Wednesday, arguing the case is distinctive enough to merit its own hearings.

The federal Liberals counter that Pallister took his flat-rate tax plan off the table before they could reshape their climate policy around it.

Last week, a federal judge set out the timelines for the Manitoba case, asking the province to submit its affidavits by the end of August and Ottawa to do the same by late November, but both a provincial and federal election will take place between the two.

It's not until the first week of 2020 that both sides will be asked to set a hearing date.

Both the Manitoba NDP and Liberals say they would scrap the lawsuit and negotiate a climate plan with whichever government is sitting.

In May, a Nanos Research poll conducted for The Globe and Mail found Prairie respondents split on whether provinces should spend their tax money fighting the federal carbon tax. Two-third of respondents nationally opposed such lawsuits.

Saskatchewan is appealing to the Supreme Court, and Higgs said New Brunswick will likely intervene in support of that province, but cancel its plans to file its own suit at home.