North and South Sudan have agreed in principle to demilitarise the disputed central Abyei region and allow the deployment of Ethiopian peacekeeping troops in the area.
South Sudan is scheduled to become an independent country on 9 July, but the status of Abyei – a fertile, oil-producing area claimed by both sides – has complicated the secession.
Khartoum sent tanks and troops into Abyei on 21 May, causing tens of thousands of people to flee and sparking an international outcry.
The announcement late on Monday came after the North's President, Omar Hassan al-Bashir, and the South's President, Salva Kiir, met in the Ethiopian capital Addis Ababa to discuss the status of Abyei and other issues in the run-up to the split.
"In principle, the parties have agreed to the demilitarisation of the area and the deployment of Ethiopian forces," said Barney Afako, spokesman for an African Union panel on Sudan. "The question of the administration of Abyei is still on the agenda."
Mr Afako said the mandate and size of the Ethiopian force were still being discussed, and that the peacekeepers would be deployed as soon as there was an agreement.
South Sudan voted to break off into a new country in a January referendum promised by a 2005 peace treaty that ended decades of civil war. Abyei was a major battleground during the conflict.