The UMA was founded on February 17, 1989, when the founding treaty of the Arab Maghreb Union was signed by the Five Heads of State in Marrakech.

The Marrakech Summit was preceded by the meeting held by the Five Maghreb Heads of State in Zeralda (Algeria) on June 10, 1988, during which it was decided to set up a Main Committee to define ways and means. allowing the realization of a Union between the Five States of the Arab Maghreb. The work of this major Commission subsequently constituted the WBU's Short and Medium-Term Work Program.

In addition to signing the Treaty, the Marrakesh Summit adopted a Solemn Declaration on the establishment of the WBU and the Union Work Program.