Article 52 Vienna Convention on Diplomatic Relations
The Secretary-General of the United Nations shall inform all States belonging to any of the four categories mentioned in article 48:
(a) Of signatures to the present Convention and of the deposit of instruments of ratification or accession, in accordance with articles 48, 49 and 50;
(b) Of the date on which the present Convention will enter into force, in accordance with article 51.
See also: Article 51 Vienna Convention on Diplomatic Relations
