"Canada's announcement that it is withdrawing from the Kyoto protocol is bad news for the fight against climate change," ministry spokesman Bernard Valero told journalists.
"It is out of the question to relax our efforts or to break the dynamic of the Durban agreement," he said.
Canada on Monday became the first country to declare it was formally exiting the pact, a reversal that will save it billions of dollars in fines, and poured scorn on the landmark treaty for hampering attempts to tackle pollution.
But the decision provoked heavy criticism, including from China which said the move went against international efforts to combat climate change.
Canada's decision follows a deal reached in Durban this month to create a roadmap that will for the first time bring all major greenhouse-gas emitters under a single legal roof. If approved as scheduled in 2015, it will become operational in 2020.
Canada agreed under the Kyoto Protocol to reduce CO2 emissions to 6.0 percent below 1990 levels by 2012, but its emissions of the gases blamed for damaging Earth's fragile climate system have instead increased sharply.
The landmark pact reached in 1997 is the only global treaty that sets down targeted curbs in global emissions.
But those curbs apply only to rich countries, excluding the United States – which has refused to ratify the accord.