Emissions of carbon dioxide in the energy sector stagnated in 2014, breaking a trend of constant increases in the last four decades, except in years of economic downturn, said the International Energy Agency.

Emissions of carbon dioxide last year remained stable at 32,300 million tons, compared to 2013, according to the IEA,

"This is a welcome and significant surprise," IEA chief economist Fatih Birol said in a statement.

"We offer more hope that humanity will work together to combat climate change, the greatest threat we face today," he added.

The IEA, which is headquartered in Paris and advises governments of developed countries, said the slowdown in the increase in emissions was linked to patterns of energy consumption kinder to the environment in China, the United States and developed countries .

"In 2014, China saw increased generation of electricity from renewable sources such as hydro and wind, and less burning of coal," he said.

Birol said the figures offer a "much needed boost to the negotiators prepare to close a global climate agreement in Paris in December: first, the emissions of gases that cause the greenhouse effect are detached from economic growth."

A summit in Paris must agree to limit emissions, a committee of UN scientists say are causing more heat waves, floods and increases the level of the oceans.

The IEA said carbon emissions stagnated or fell only three times in the last forty years for which information is available, and always linked to economic downturns: in the early 1980s, in 1992 and 2009.

In 2014, the world economy grew by 3 percent