The ninth additional protocol was adopted at the XXVI Congress of the Universal Postal Union in Istanbul (Turkey) on 6 October 2016.

Uzbekistan has been a member of the Universal Postal Union since 1994 and is actively involved in its activities. The Charter itself is the main act regulating the work of this organization. Changes to the Charter are formalized by an additional protocol, which is adopted by the Union Congress, consisting of representatives of member countries.