South Sudan is due to secede on July 9, but the split has been complicated by unresolved questions such as how to share oil revenues and the exact position of the common border.
Tensions between north and south flared after Khartoum occupied the fertile, oil-producing Abyei region on May 21, and has refused calls from the United States, United Nations and southern officials to withdraw.
Fighting has also continued for nearly a week between the northern army and south-aligned armed groups in the northern oil state of Southern Kordofan, which borders the south.
Sudan’s President Omar Hassan al-Bashir and south Sudan’s President Salva Kiir will meet in Addis Ababa “to review the pending issues, especially the situation in Abyei”, Sudan’s state news agency SUNA said.
Ethiopian Prime Minister Meles Zenawi and former South African President Thabo Mbeki will also participate in the talks, SUNA said.
Southerners voted to secede in a January referendum, the culmination of a 2005 peace deal that ended decades of north-south civil war.