Abyei status referendum, 2011

The Abyei status referendum is a delayed referendum that was originally due to be held in 2011 in which the residents of Abyei can decide either to remain part of the Sudanese South Kordofan region or to become part of the Bahr el Ghazal region of South Sudan.

The referendum was originally planned to be held simultaneously to the 2011 Southern Sudanese independence referendum on January 9–15, 2011, but was postponed indefinitely due to disagreements over the process. Due to the uncertainty, violence erupted in which more than 30 people were killed. As a response the UN deployed extra troops to its UNMIS contingent The impasse on the referendum is due to lack of agreement on who constitutes a "resident of Abyei". The question is whether to include the Messiria tribe, who have historically stayed in the region every year for six months.

On 24 October 2012, the African Union proposal was to hold a referendum in October 2013, in accordance with the endorsement from the African Union Peace and Security Council following a mediation team led by former South African President Thabo Mbeki that included the exclusion of the Messiria, until Sudan rejected the offer saying it was sovereign over the region and that such a demarche would threaten the entire conflict resolution process. It also offered a six-week delay, until 9 December, to agree to the terms of a referendum between Sudan and South Sudan. Sudanese Foreign Minister Ali Karti said that he had confidence that the AU would accord both states more time to resolve difference over organising the referendum. He told the Sudanese parliament, in particular MPs from South Kordofan, that the AU proposal "will not ever see the light of day" and it will not be referred to the United Nations Security Council as the United States of America wants."

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