CO2 emissions were 32.3bn tonnes in 2014, unchanged on 2013’s figure, said the IEA quoting preliminary data.

The body said the flat-lining of emissions last year is the first such event for 40 years that is not linked to an economic downturn.

Unlike previous reverses in carbon emission, it came against the background of a 3% expansion in the global economy.

The organisation cited changes in the energy mix in China – which is generating more power from renewables – as one of the factors behind the development, which suggests “efforts to mitigate climate change may be having a more pronounced effect on emissions than had previously been thought”.

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