Agreement (with exchange of letters) concerning the relationship between the United Nations and the International Atomic Energy Agency. Approved by the General Conference of the International Atomic Energy Agency on 23 October 1957 and by the General Assembly of the United Nations on 14 November 1957 = Accord (avec e?change de lettres) re?gissant les relations entre l'Organisation des Nations Unies et l'Agence internationale de l'e?nergie atomique le 23 octobre 1957 et par l'Assemble ge?ne?rale des Nations Unies le 14 novembre 1957.