Banks with more than $47tn collectively in assets signed on to the United Nations-backed Principles for Responsible Banking (PRB) framework for climate action rolled out this week. Yet only three of the world’s 10 largest banks joined the coalition of 130 signatories.

Citigroup, Mitsubishi and Industrial and Commercial Bank of China joined the pledge, which includes six principles, the first one asking firms to self-grade sustainability practices. Some of the signatories to an earlier pact, and those abstaining this time, said that the principles are too vague, a Financial Times opinion piece said.