ExxonMobil and ConocoPhillips are the US oil majors most exposed to political action on climate change because of their failure to diversity into alternative energy sources — with one needing to cut production by 85% to keep CO2 emissions within internationally agreed limits.

That is according to the latest report from Carbon Tracker, a “financial think-tank” that specialises in analysis of the impact of climate change. It found that, as a group, the world’s listed oil and gas companies would have to cut production by 35% on average in the next two decades to keep emissions within these limits.