Global carbon dioxide emissions levelled off at 32.3 megatonnes in 2014, the International Energy Agency reported Friday, “marking the first time in 40 years in which there was a halt or reduction in emissions of the greenhouse gas that was not tied to an economic downturn.”

Emissions held steady in spite of worldwide economic growth of 3%, largely due to changes in energy consumption patterns in China and OECD countries. “This gives me even more hope that humankind will be able to work together to combat climate change, the most important threat facing us today,” said IEA Chief Economist and incoming Executive Director Fatih Birol.

Key factors in stabilizing emissions included China’s decision to use more renewable energy and burn less coal, states an IEA release. In OECD economies, meanwhile, “recent efforts to promote more sustainable growth—including greater energy efficiency and more renewable energy—are producing the desired effect of decoupling economic growth from greenhouse gas emissions.”

“This is both a very welcome surprise and a significant one,” Birol said. The decoupling of emissions and growth “provides much-needed momentum to negotiators preparing to forge a global climate deal in Paris in December.”

But Executive Director Maria van der Hoeven added that “this is no time for complacency – and certainly not the time to use this positive news as an excuse to stall further action.”