The recent codifications of international treaties, for example the Vienna Convention on the Law of Treaties in 1969,determine that in order to apply such conventions, the expression “international organization” must be interpreted as an intergovernmental organization. This way it can be distinguished the international organizations with legal personality in Public International Law and non-governmental organizations that, in spite of their similar action line or structure.
However, all these definitions areway too simple to elucidate what is a international organization to International Law. For that reason, the concept that is majorly accepted for the legal doctrine brings a definition formulated during the workshop of codification of treaties law, according to which an international organization is a “association of State-nations, constituted by treaty, with common constitution and organs and of alegal personality distinct of the State-members” (DINH; DAILLIER; PELLET, 2003, p. 592).
Until 20th century, only State-nations were owners of legal personality in International Law. For many years it was discussed if international organizations would be subjects of International Law. Thus, international legal personality was not an attribute granted to international organizations, mainlybecause they did not had an influence of great impact in the legal area.
During 20th century, international organizations played an important role regarding the development of International Law, and, as time passed, they acquire legal personality. On the other hand, there is still the debate of how long will this kind of personality reach. Michael AKEHURST (1985) points out that “when the statescreate an international organization, they establish it for specific ends, granting, therefore, limited powers. For this motive, the notion of legal personality must be considered as a relative and non absolute concept.”19
The United Nations Chart, in its article 104, determines that State-members must endow to the United Nations Organization (UN) the legal capacity to exercise its faculties withinits field of action.
It is important to say that the UN Chart does not literally express the attribution of international legal personality. The articles 104 and 105 of that Chart refer to the legal capacity of the organization inside territory and regarding States-members internal law. SORENSEN (1973), observes that this legal capacity may be not a characteristic but a limit of action ofinternational nations.
Los instrumentos constituyentes de las instituciones internacionales conmúmente no contienen una autorización general para que la organización celebre tratados, pero muchos de éstos las autorizan para celebrar tratados de cierto tipos. (...) Lo cierto es que en los años que siguieron a la segunda Guerra Mundial, la práctica de las instituciones internacionales en el campo delderecho de los tratados ha crecido extensamente. (...) También debe notarse que las instituciones internacionales, cuyas constituciones no autorizan la conclusión de tratados de ninguna clase, no obstante han celebrado algunos con Estados (acuerdos sobre la sede de la organización), y con otras instituciones internacionales en materia de cooperación.(21)
Michael AKEHURST (1985) says that an...