STRATFORD, Ont. - Ontario will soon unveil an "aggressive'' plan to reduce greenhouse-gas emissions that Premier Dalton McGuinty said Tuesday will not come at the cost of the province's struggling auto industry.

The province's Environment Ministry is "mulling over'' advice from various groups, including the auto sector, and will soon reveal a plan that the premier promised will "challenge Ontarians'' to find home-grown solutions to the climate-change problem.

"The evidence is in now,'' McGuinty said following the announcement of a $1.7-million loan to FAG Aerospace in Stratford, Ont.

"There is simply no longer any doubt that, as a species, we are actually influencing our weather in a harmful way. It's time for us to assume our responsibility and we look forward to putting forward an aggressive plan, an ambitious plan.''

While McGuinty said the plan will challenge all industrial sectors, he promised it won't hurt the beleaguered auto industry, which continues to reel from layoffs and restructuring.

Last October, McGuinty said Ontario couldn't risk losing "good, high-paying jobs'' when the federal government mused about imposing stricter vehicle emission standards to cut greenhouse-gas emissions.

But McGuinty now says Ontario doesn't have to choose between a greener environment and a thriving economy.

"We can take on this responsibility in a way that is good for the economy,'' he said. "It's a false choice to think that somehow we have to choose between economic growth and a safe and sound environment.''

Ontario can cut its harmful emissions by investing more in public transit and helping people make more energy efficient decisions, he said. If everyone simply replaced an old lightbulb with an energy-efficient one, McGuinty said the province could shut down one coal-fired power plant.

The Liberals initially promised to shut down Ontario's coal-fired plants by 2007 but have since delayed the closures. Dan McDermott, director of the Ontario chapter of the Sierra Club of Canada, said fulfilling that election promise alone would have cut the province's greenhouse-gas emissions drastically.

If Ontario wants to make a real dent in its harmful emissions, McDermott said McGuinty has to close the plants, make building codes more energy efficient and impose vehicle emission standards which are already in place in California.

"This is not something that would be an act of political bravery,'' he said.

Talk of strict vehicle emission standards gives the precarious auto industry jitters, but Canadian Auto Workers president Buzz Hargrove said he's confident McGuinty won't do anything to hurt the sector further.

"There is enormous uncertainty in our workplaces today and if somebody does something stupid, they pay for that,'' Hargrove said. "I don't think the premier is stupid.''

There are alternatives to tougher emission standards, he said. The province could invest in public transit and give cash incentives to motorists who scrap their old cars for new ones, Hargrove said.

Ontario could also set targets for automakers to make their cars more fuel efficient, he added.

Keith Stewart, manager of the climate change program at the World Wildlife Federation, said Ontario has a long way to go if it's going to make a dent in greenhouse gas emissions.

British Columbia and Quebec both have plans to reduce their emissions below 1990 levels, which helps meet Canada's commitment under the Kyoto accord, he said.

Both provinces give tax exemptions for fuel-efficient cars, are tightening up vehicle emission standards and will mandate the construction of more energy efficient buildings, Stewart said.

"The bar is being raised for Ontario,'' he said.

But New Democrat Peter Tabuns, who tabled a private members' bill on climate change in December, said the Liberals are just trying to paint themselves green in the run-up to the October election.

"You know it's an election year when the premier starts talking about a Kyoto plan,'' said Tabuns, a former director of Greenpeace.

"They've been reading the polls and they see they have a credibility problem. I'm a bit cynical.''