For the green investor, targets do not come much bigger than ExxonMobil. And the Church of England is now embroiled in a fight against the largest American oil company over its disclosure of carbon emissions.

In January, the Church Commissioners - the body that manages the Church's £6.7 billion investment fund - announced that, for the first time, it was going to file a shareholder resolution in the US. At the ExxonMobil annual general meeting, expected in May, it would call on the company to show it is doing more to "prepare for a low-carbon future".