90 An outstanding form of international activity on the part of Christians is found in the joint efforts which, both as individuals and in groups, they contribute to institutes already established or to be established for the encouragement of cooperation among nations. There are also various Catholic associations on an international level which can contribute in many ways to the building up of a peaceful and fraternal community of nations. These should be strengthened by augmenting in them the number of well qualified collaborators, by increasing needed resources, and by advantageously fortifying the coordination of their energies. For today both effective action and the need for dialogue demand joint projects. Moreover, such associations contribute much to the development of a universal outlook—something certainly appropriate for Catholics. They also help to form an awareness of genuine universal solidarity and responsibility. Finally, it is very much to be desired that Catholics, in order to fulfill their role properly in the international community, will seek to cooperate actively and in a positive manner both with their separated brothers who together with them profess the Gospel of charity and with all men thirsting for true peace. The council, considering the immensity of the hardships which still afflict the greater part of mankind today, regards it as most opportune that an organism of the universal Church be set up in order that both the justice and love of Christ toward the poor might be developed everywhere. The role of such an organism would be to stimulate the Catholic community to promote progress in needy regions and international social justice.
Source: Gaudium et Spes (Vatican.va)