Historically, climate governance initiatives and associated scholarship have all but ignored the potential for Bglobal moral norms^to bring about changes in the political conditions for global climate mitigation. This is surprising, since global moral norms are widely employed-as both a mode of governance and an analytical framework-in other domains of global governance, from international security to human rights. However, recent national-level fossil fuel divestments, moratoria on new coal mines and bans on gas fracking, among other developments, suggest the promise of global moral norms prohibiting fossil fuel-related activities, which this article terms Banti-fossil fuel norms^(AFFNs). The article interprets recent examples of such activities in the light of international relations theory on moral norms to provide a general framework for understanding how AFFNs originate, spread and affect states. Specifically, the article argues that there are: (i) influential agents that are originating, and likely to continue to originate, AFFNs; and (ii) international and domestic mechanisms by which AFFNs are likely to spread widely among states and have a significant causal effect on the identity-related considerations or rational calculations of states in the direction of limiting or reducing the production or consumption of fossil fuels. The article also shows that, because they spread and affect state behaviour through mechanisms of Binternational socialization^and domestic Bpolitical mobilization^, AFFNs cohere with and build upon the new paradigm of global climate governance crystallized in the Paris Agreement. AFFNs, the article concludes, represent a promising new frontier in climate governance.