Oil company chiefs are well-versed in preaching on green virtues even as they step up exploitation of oil and gas in pursuit of profit - but someone higher up is watching.

Pope Francis last weekend delivered a damning sermon on the evils of environmental pollution and the threat of global warming for a distinguished audience of top oil executives that gathered at the Vatican in Rome.

The pontiff warned of the need to convert to clean fuels to avert a climate catastrophe, stating that “energy use must not destroy civilisation” and urging an energy shift to combat emissions and eliminate poverty.

Francis wrote a treatise in 2015 entitled Laudato Si (Praise Be) on protecting the environment from global warming but told the assembly in the Pontifical Academy of Sciences it was “worrying” there was a continued search for fossil fuels, perhaps pricking the consciences of some congregants.

He called for measures such as carbon pricing and transparency on climate risk to aid a transition to a low-carbon world to curb the global temperature rise to 1.5 degrees Celsius in line with the Paris climate accord, with only 12 years left to achieve this goal.

Among the listeners were chief executives from oil giants ExxonMobil, BP, ConocoPhillips, Eni and Equinor, who may claim they are singing from the same hymn sheet.

But critics point out such companies are also spending billions of dollars to find more oil and gas even as scientists say combustion of fossil fuels found to date already exceeds levels needed to maintain a stable environment and needs to stop by 2050.

So, perhaps oil bosses will at that time all be invited back by the Catholic leader - this time for confession.

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