Sean Kilpatrick, The Canadian Press
Prime Minister Stephen Harper responds to a question during question period in the House of Commons on Parliament Hill in Ottawa on Monday, June 2, 2014.
OTTAWA - The federal government is responding to U.S. President Barack Obama's latest climate-change plan with a simple message: been there, done that.
But critics and observers of environmental policy say the United States is taking a big leap ahead of Canada in meeting its emissions targets for 2020.
The U.S. Environmental Protection Agency plan would place new regulations on existing coal-fired electricity plants starting in 2020.
Prime Minister Stephen Harper says Canada took similar action on coal in 2012, and the impact on carbon emissions is likely to be greater.
The opposition and others say the situations are not the same: coal is the biggest source of emissions in the United States, while Canada's biggest polluter is the oil and gas sector.
The Conservative government has long promised, but has not yet introduced, regulations on oil and gas emissions.