The United States was one of a handful of countries to meet Tuesday's March 31 target for submitting emissions reduction pledges ahead of next December's United Nations climate summit in Paris, known as COP21.
But after two decades of Canadian governments loudly asserting that a continental approach to climate targets is critical to North America's integrated economies, the silence from Ottawa on this year's global climate conference has been deafening.
Under NDP questioning in the House of Commons, Environment Minister Leona Aglukkaq said she welcomed the aggressive U.S. targets, but didn't commit to match them.
"We have always said to effectively reduce global greenhouse gas emissions, all major emitters must be on board," Aglukkaq said.
Rather than common Canada-U.S. emissions targets, a spokesman for the minister later said in an email: "The government has been clear that the integration between our two economies means that the United States and Canada should co-ordinate on regulatory approaches where appropriate."
The U.S. proposal has drawn intense interest around the world. The White House hopes to increase pressure on other countries to announce equally ambitious goals.
Most countries missed Tuesday's informal UN deadline. The European Union, Switzerland, Norway, Mexico and Russia have also submitted contribution targets to date.
Nonetheless, New Democrat Megan Leslie accused the Harper government of acting like "the worst student in the class" by failing to produce a Paris target this week.
"We will submit Canada's greenhouse gas emissions targets in the weeks ahead and we are seeking information from the provinces and the territories on how they will meet their targets," Aglukkaq responded.
At least one province, however, is unhappy with the current federal consultations.
David Heurtel, Quebec's environment minister, said in an interview that he has been rebuffed in his efforts to get a meeting with Aglukkaq to discuss the Paris targets.
"We have not been able to have any kind of response from Ottawa on that request to just sit down and work with the federal government in a collaborative way to achieve a common contribution," said Heurtel, who added "this position is shared by many provinces and territories."
"We don't know what the federal government intends to do on this topic and for us that's a serious concern."
Aglukkaq's office shot back: "We are continuing to engage in an open dialogue and have not yet received quantifiable data from Quebec."
When the Kyoto Protocol was signed in 1997, then-prime minister Jean Chretien and U.S. president Bill Clinton agreed to matching emissions targets, just as Stephen Harper did with Barack Obama on the Copenhagen Accord in December 2009.
Canada is not on track to meet its 2020 Copenhagen commitments, just as it came nowhere near hitting its Kyoto targets under the Liberals before the Harper government finally withdrew from that international agreement in 2011.
Nor are the provinces and territories on track to meet their own emission reduction targets.
Keith Stewart of Greenpeace Canada issued a release accusing the Conservatives of "acting as the lobbying arm of the tar sands industry in international climate negotiations" and demanding the government match or exceed the U.S. emissions cuts.
"Failure to do so would mean Canada gets left behind as other countries reap the environmental, economic, and human benefits of a transition away from fossil fuels," said Stewart.
Elliot Diringer of the Virginia-based Center for Climate and Energy Solutions said the Canadian government, unlike President Obama's executive orders, is counting on provincial actions to help build its national emissions profile.
"Those, structurally, are two different approaches," said the former White House senior policy adviser.
He noted there is still plenty of time to submit targets, but added "there's strong pressure on the other major emitters to step up soon, including Canada."
— With files from the Associated Press
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