The African Union has readmitted Morocco into the bloc 33 years after its withdrawal over the still existing Western Sahara dispute.

The majority of the AU member states voted for the re-admission of during the 28th summit in the Ethiopian capital Addis Ababa on Monday, leaving the issue of the disputed territory of Western Sahara for another day.

"Morocco is now a full member of the African Union. There was a very long debate but 39 of our 54 states approved the return of Morocco, even if the Western Sahara question remains," Senegalese President Macky Sall told reporters.

"As we have said, if the family grows bigger, we can find solutions as a family," Macky Sall added.

Algeria and South Africa were among the heavyweights that opposed the re-admission of Morocco.

The country withdrew from the AU in 1984, when the mineral-rich and sparsely populated Saharan Arab Democratic Republic (SADR), commonly known as Western Sahara, was accepted as a member.

Morocco annexed Western Sahara, a former Spanish colony, in 1975. It maintains that Western Sahara is an integral part of the kingdom, but the international community has not recognized the annexation. Western Sahara is home to the Algerian-backed Polisario Front, a Sahrawi rebel national liberation movement aiming to end Moroccan presence in the territory.