The armed dispute between the Government of Sudan and the Government of Southern Sudan over the Abyei region has led to the displacement of at least 40,000 people and threatens to unravel the gains of six years of peace in Sudan.
The current crisis began last week when Southern troops fired on Northern troops redeploying out of the region. Khartoum responded with a military take-over of the region. The UN estimate that 40,000 Abyei residents have fled and the Sudan Armed Forces (controlled by Khartoum) have been filmed burning villages and have defied calls from the international community to leave.
Southern Sudan's President Kiir has stated that he will not go back to war with the north, while President Bashir has said he is neither scared of American sticks nor interested in their carrots. The prospects for a quick resolution do not look good.
Abyei: North or South?
The crisis is the result of a failure to implement the provisions of the Comprehensive Peace Agreement (CPA) on Abyei. Under the CPA Abyei was supposed to vote in a referendum on whether to remain in Northern Sudan or join the South.
The first challenge was agreeing the boundaries of Abyei. The parties resorted to arbitration by the Permanent Court of Arbitration but neither party could agree on who constituted a resident of Abyei - the South argued for only permanent residents, likely to vote to join the South, while the north wanted to include nomads who pass through each year and would likely vote to remain in the north.
Efforts by the United States and the African Union to come up with a compromise have not been successful and have particularly alienated southerners, who felt that US proposals to further divide Abyei benefited northern interests.
Potential threats to peace
The crisis over Abyei may point towards future problems. Abyei is not the only CPA issue that has been left until the last moment to be resolved. The North - South border is still not demarcated, oil revenue from Southern oil is currently split 50/50 and agreement has not yet been reached on how this relationship will work after independence, and the status of Sudan People's Liberation Movement leaning areas in the North - Southern Kordofan and Blue Nile State - have yet to be fully addressed.
These unresolved issues leave scope for future disputes and bad blood. The international community were distracted following the signing of the CPA by events in Darfur, and for several years implementation of clauses slipped. It is only recently that momentum has picked up. International pressure has been important in getting the parties to talk.
The practice of brinkmanship and leaving issues to the last possible moment means that crucial issues will still be unresolved when South Sudan becomes independent on 9 July. Abyei serves to remind Sudan's partners that peace between the north and south is by no means secure.
Prospects of a resolution
The principles of the CPA offer the best hope for a sustainable peace. International pressure on Khartoum, focussing on a return to last week's status quo, would allow talks on the future of Abyei to resume and perhaps then produce a sustainable and popularly legitimised solution.
Khartoum protests that it is no longer concerned with normalising relations with the US and will not leave Abyei. But the prospect of lifting US sanctions, being removed from the list of State Sponsors of Terrorism and re-integration into the international community is a powerful bargaining chip to convince Khartoum to pull back.