اتفاقية السلام الشامل
Surur founded the party in 1984. After the signing of the Comprehensive Peace Agreement in Nairobi, Kenya, the party supported the Sudan People's Liberation Army/Movement (SPLA/M) in their vision of a new Sudan. The USAP represented the main support to the government during 21 years and therefore they played a major role in resolving the conflict through participating in the peacemaking and peace-building processes of the Comprehensive Peace Agreement. Before it was dissolved, the party was represented by four seats in the government of South Sudan.