Teams from both sides are reported to have flown to the Ethiopian capital to restart the African Union-led talks which were stalled by heavy clashes last month, the worst fighting since the South won independence last July.
Tensions remain high, but Southern President Salva Kiir stressed ahead of the talks that “amicable dialogue on the outstanding issues with Khartoum is the only option for peace”.
Southern claims on Monday that troops had clashed on the border with the north after three days of air strikes and long range artillery bombardment overshadow the talks, despite Khartoum’s repeated denials of the attacks.
“They are bombing South Sudan, attacking South Sudan, and continuing to send armed groups to destabilise South Sudan… these are not the signs of peace,” South Sudan’s negotiator Pagan Amum said as he set off for the talks.
The UN Security Council earlier this month ordered both sides to cease fighting and return to talks or face possible sanctions.
Sudan denied the reported attacks, which were not possible to confirm independently. It has in turn accused the South of alleged cross-border incursions, which it said broke the UN order to halt hostilities.
Khartoum, in an apparent peace gesture, has promised to end a year-long occupation of the contested Abyei region, a Lebanon-sized area whose ownership is a key issue for Juba and Khartoum. Troops were due to pull out on Tuesday.
Sudanese troops stormed the region in May 2011, forcing some 110,000 people to flee southwards, where the majority remain in impoverished camps.
“Sudan decided to redeploy the troops out of Abyei area to offer a good environment for the talks,” Sudanese army spokesman Sawarmi Khaled Saad said in a statement.
However, he said the troops would pull out on condition Khartoum received a “guarantee” the area is part of its territory.
Abyei was to have held a referendum in January 2011 on whether it belonged with the north or South, but that ballot was stalled over disagreement on who could vote, and Juba is highly unlikely to agree to relinquish its claim.
However, Southern negotiators said they are hopeful the negotiations would produce results.
“We are actually more optimistic than any time before, as today we have the UN Security Council resolution giving a timeframe to achieve resolution within three months,” Amum added. “It is good there is international backing.”
Khartoum has said “security issues should be addressed first,” according to the Sudanese Media Centre (SMC), which is close to the security apparatus, adding that it is unhappy with Southern maps marking contested regions as their territory.
South Sudan broke away from Sudan in July after a 2005 peace deal ended one of Africa’s longest civil wars, which killed about two million people.
But tensions soon flared again over a series of unresolved issues, including the border, the future of disputed territories and oil.