G-77 summit is a forum of :

TThe Group of 77 (G-77) was established on 15 June 1964 by seventy-seven developing countries signatories of the “Joint Declaration of the Seventy-Seven Developing Countries” issued at the end of the first session of the United Nations Conference on Trade and Development in Geneva.  There were 77 founding members of the organization, but by November 2013 the organization had since expanded to 134 member countries to articulate and promote their collective economic interests and enhance their joint negotiating capacity on all major international economic issues within the United Nations system, and promote South-South cooperation for development.