REGINA - Saskatchewan Premier Brad Wall came out swinging Friday against the federal government's intention to impose a carbon tax, questioning whether it would be legal and whether Ottawa did its homework before announcing its plans.

"This is a fight for Saskatchewan's interests," Wall said at the legislature.

The federal plan announced this week by Prime Minister Justin Trudeau calls for a $10-per-tonne tax on carbon starting in 2018 and increasing to $50 per tonne by 2022.

Trudeau also said carbon pricing will be imposed on provinces that don't implement the tax or bring in a cap-and-trade system, in which industries are allotted permits for emissions that they can buy and sell.

Wall said he has asked his Justice Department to explore the province's legal options.

"The question I have is, how, if there are two or three or one province at the end of the day, that says, 'We're not doing it,' and the federal government wants then to develop and levy their own federal tax, how do they do it on one province?" said Wall.

"We're going to find out the answers to those questions and if we have to go to court, we would go to court."

The issue has divided the provinces.

Nova Scotia Premier Stephen McNeil has also been a vocal critic of the federal plan and Yukon's Darrell Pasloski remains dead set against the idea.

Alberta Premier Rachel Notley has said she isn't interested in presenting a united front with Wall and McNeil, because Alberta supports the idea of a national price on carbon in principle.

Quebec and Ontario welcomed the new federal policy.

Trudeau promised all revenue generated by a carbon tax would flow back to the province or territory from which it came. Federal Environment Minister Catherine McKenna said it would be up to provincial premiers to decide how to spend that money.

But Wall said the tax would mean fewer jobs and less pay for those in agriculture, mining and oil and gas industries.

Wall said he asked Trudeau in a phone conversation after the announcement for an economic assessment to show the tax's impact.

"It's not there. The bottom line is, they haven't done it," said the premier.

"How can you announce a major tax like this, that we know will have an impact on jobs, that we know will cost Canadians a lot of money in their household budgets — eventually someone's paying — how can you do that without an economic assessment?"

Canada generates 1.6 per cent of the world's greenhouse gas emissions. Saskatchewan accounts for 10 per cent of the Canadian amount, about 75.5 million tonnes annually.

The province relies heavily on coal for power. SaskPower, the Crown utility, announced plans last November to have up to 50 per cent of power come from renewable sources by 2030.

SaskPower has also put about $1.5 billion into a carbon capture and storage project at a coal-fired power plant.

Wall said technological solutions like that, along with adaptation, are a better approach to addressing climate change.

"We've made the largest public sector investment in technology that actually does something about it — not tax schemes, not cap-and-trade, not pricing carbon."

News from © The Canadian Press, 2016