Sudan and South Sudan split a year ago under a 2005 peace deal that ended decades of war, but have yet to work out a variety of issues such as the exact position of the border.

They are expected to come under international pressure to reach at least a partial deal on border security in the new round of talks which should clear the way to resume oil exports vital to both economies.

Sabir Hassan, co-chair of Sudan's economic negotiations team, said the talks, due to take place in the Ethiopian capital where the African Union is based, had been postponed until after the September 2 funeral of Meles Zenawi who died last week.

Sudan's foreign ministry said earlier this month talks would restart on Aug 26 but delegates from both sides are now due to arrive in Addis Ababa on September 3 for negotiations starting the following day, Hassan told Reuters.

Sudan and South Sudan reached an interim agreement this month on a dispute over oil payments. But Sudan has said it wants a deal to guarantee security along the border before South Sudan starts pumping oil again via Sudan for export.

Among the main points to be addressed in the talks is the demarcation of the border, along which at least five areas are disputed.

Sudan also wants assurances Juba will end support to rebels of the Sudan People's Liberation Movement-North (SPLM-North) operating in the border states of South Kordofan and Blue Nile.

Juba denies any link to the SPLM-North but many analysts and diplomats say Khartoum's claim is credible.