Canada announced Friday it aims to reduce its greenhouse gas emissions by 30 percent from 2005 levels by 2030, after saying it would miss an earlier, less ambitious goal.

This new target would be reached in part by regulating methane discharges in the oil and gas sector, natural gas power plants as well as the chemicals and nitrogen fertilizer industry.

"This target is fair and ambitious," Environment Minister Leona Aglukkaq told a nationally-televised press conference.

It follows an earlier goal, which Ottawa has said it would miss, of reducing emissions by 17 percent by 2020.

And it was immediately criticized by environmental activists as the weakest pledge -- up to three times weaker -- of any industrialized nation ahead of a Paris climate summit in December.

"Canada's climate target is less than meets the eye and another disappointing sign of its reluctance to fight climate change," said Danielle Droitsch of the Natural Resources Defense Council.

Dale Marshall of Environmental Defense said the target "will further cement Canada's global reputation as a climate laggard."

French President Francois Hollande has set out an ambitious goal for the Paris meeting: an agreement to limit the rise in global temperatures linked to greenhouse gas emissions to two degrees Celsius (3.6 Fahrenheit) from the pre-industrial age.

- Canada, US diverge -

A recent government report noted that Canada is one of the highest per capita CO2 emitters, due to "its size, climate (i.e. climate-driven energy demands) and resource-based economy," but added that it represents less than two percent of global emissions.

The US government has formally pledged to reduce greenhouse gas emissions by 26-28 percent from 2005 levels within the next decade.

The European Union, meanwhile, is planning to go even further with deeper cuts.

Until now, Ottawa has favored a continental approach to reducing greenhouse gas emissions, aligning measures with its neighbor and biggest trading partner, the United States.

Initiatives have included curbing emissions from the transportation and electricity sectors -- two of Canada's largest sources of emissions.

But the most recent emissions data, revised under new UN reporting rules, shows total Canadian emissions have risen 18 percent since 1990 to 726 megatons in 2013.

Aglukkaq said the government would continue its "sector by sector regulatory approach that protects the Canadian economy."

But, she added, it would start to distance itself from Washington on new measures to curb global warming.

- Feds versus provinces -

In order to achieve its new target, Ottawa will arguably have to co-operate with regional governments with whom they share constitutional authority over environmental regulations.

But tensions between the federal government and governing authorities in Canada's 13 provinces and territories are currently high.

Last month, Prime Minister Stephen Harper expressed his strong opposition to carbon taxes just as Ontario province introduced a cap and trade scheme to curb CO2 emissions.

The system would cap the amount of carbon dioxide gas emitted by each industry, and allow firms to buy and sell unused emissions quotas under an imposed ceiling.

Ontario joined Quebec and California under the Western Climate Initiative, allowing companies in these jurisdictions to trade emissions credits.

The west coast province of British Columbia is also a WCI member but has imposed a carbon tax instead of credits.

With Ontario's introduction of a cap and trade system, more than 75 percent of Canadians now live in a jurisdiction with some form of carbon pricing.