“We are invoking Canada’s legal right to formally withdraw from Kyoto,” Environment Minister Peter Kent said following a marathon Un climate conference in South Africa, at which nations agreed to a new roadmap for worldwide action.

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.

“ Kyoto is not the path forward for global solution to climate change,” Kent said. “If anything, it’s an impediment. Canada agreed under the Kyoto Protocol to reduce CO2 emissions to 6.0% below 1990 levels by 2012, but its emissions of the gases blamed for damaging Earth’s fragile climate system have instead increased sharply.

Saying the targets agreed to by a previous Liberal administration were unattainable, Conservative Prime Minister Stephen Harper’s government last year unveiled its own measures aimed at curbing emissions, in line with US efforts. Pulling out of Kyoto now allows Canada to avoid paying penalties of up to $13.6 billion for missing its targets.