Global greenhouse gas emissions are likely to rise to record levels in the next two years, as governments fail to “build back better” from the Covid-19 pandemic and projects to develop new technologies such as small modular reactors and clean hydrogen face logistical and cost challenges.

Emissions will rise again this year and next year, after a fall last year, and 2023 is now on track to see the highest levels of carbon dioxide output in human history, equalling or surpassing the record set in 2018, according to forecasts released by the International Energy Agency.

Such a rise would put the goals of the 2015 Paris climate agreement all but out of reach, as scientists have warned that emissions must halve this decade if the world is to limit global temperature rises to 1.5C, beyond which the effects of climate breakdown will ravage swathes of the globe.