Universal Postal Union (UPU), is a specialised agency of the United Nations that aims to organise and improve postal services as well as to ensure collaboration in this sector globally.
The Constitution is the basic Act of the Union and it contains organic rules of the Union and is not subject to reservations.
The Universal Postal Convention and its Regulations embody the rules applicable throughout the International Postal Service and the provisions concerning the letter-post and postal parcel services. These Acts are binding on all member countries. Thus, member countries must ensure that their designated operators filfill the obligations arising from the Convention and its Regulations.
An international convention or treaty is an agreement between different countries that are legally obligatory to the contracting States.
Download UPU Regulation to the Convention document.