Canadians are “punching below our weight” on climate change and Prime Minister Stephen Harper squandered an opportunity to lead at Copenhagen, charges Premier Dalton McGuinty.

In his most candid remarks since world leaders last Friday concluded a summit on greenhouse gas emissions with a noncommittal three-page pact that sets no long-term reduction targets, the premier lambasted Ottawa.

“It was a missed opportunity for us as people, as a species, frankly,” he said in an interview with Global News’ Focus Ontario to be broadcast Saturday at 6:30 p.m.

“We failed to find a way to come together and, in a sincere and determined fashion, come to grips with a global threat — climate change.

“Something has been put in place (but) it is not legally binding. Hopefully, discussions over the next year or two will lead to something that is binding.”

In a separate interview with CTV News, Prime Minister Stephen Harper told Robert Fife and Lloyd Robertson that Canada cannot act unilaterally on climate change.

“If the Americans don’t take realistic actions on emissions, it’s difficult for Canada to do much because, quite frankly, factories and economic activity will simply relocate south of the border if the Americans are not harmonized with us,” said Harper.

McGuinty said he and Quebec Premier Jean Charest are preparing “our people for a post-carbon world, or at least a carbon-constrained world.”

“That’s why, here in Ontario, we’re shutting down coal-fired generation (by 2014). We have found all kinds of new opportunities in this world through our Green Energy Act. It’s going to create 50,000 jobs for us.”