I thought BRICS was just an identifier for "the fastest developing economies", but I looked it up and found they've started signing treaties between them. Wikipedia:

The BRICS were originally identified for the purpose of highlighting investment opportunities and had not been a formal intergovernmental organization. Since 2009, they have increasingly formed into a more cohesive geopolitical bloc, with their governments meeting annually at formal summits and coordinating multilateral policies; China hosted the most recent 14th BRICS summit on 24 July 2022. Bilateral relations among the BRICS are conducted mainly on the basis of non-interference, equality, and mutual benefit.