I worked for a few years on highlighting the UK Treasury’s critical role in enabling or – more usually – blocking green economic transformation. Here’s a piece I wrote for OpenDemocracy about it in 2014.
https://www.opendemocracy.net/en/opendemocracyuk/transforming-treasury-biggest-and-best-idea-of-all/
The Treasury is the spider at the heart of the Government web. It holds the purse strings and takes pride in saying ‘no’ to requests for spending. And it’s guardian and promulgator of Whitehall’s economic thinking: whatever the Government in general thinks about markets, regulation, externalities and economic modelling, it thinks it from here.