It's tricky finding anything out about a lot of places. If you're interested in investments instead of savings, you could look at ESG funds. They generally have mandates to avoid fossil fuel investments.
Though in my experience, it just means more tech stocks!
BristolPost seems to have an article with a reasonably up-to-date list of a lot of places. https://www.bristolpost.co.uk/news/uk-world-news/climate-change-list-uk-banks-8396310
(And yes, the locking of subs...It still all needs working out. Moderators are not set in stone. I've popped up an alternative for now, still need to get all the information together: https://feddit.uk/c/personalfinance )