The talks in the capital Addis Ababa will “probably” take place on Sunday, Barnaba Marial, the South Sudanese government spokesman told journalists late Friday.
Sudan’s official news agency SUNA said Bashir would leave for the talks on Sunday.
Negotiations between the two neighbours, which resumed early this month, have focused on oil, border issues and the disputed Abyei area.
The European Union’s top diplomat Catherine Ashton welcomed news of the Addis Ababa meeting and urged “both governments to conclude a comprehensive agreement on all outstanding issues”.
In a statement she said the two neighbours had already made significant progress, notably on oil and security issues.
“It is now for the two governments to build on the progress achieved … and agree on the few remaining issues, including a safe demilitarised border zone,” she said. “This summit is a unique opportunity to set their countries on the path to peace and prosperity, based on the concept of two viable states.”
Marial said the common border, which closed to most vehicles in June of last year, has now reopened.
“Yes the flights have now opened Juba-Khartoum, Khartoum-Juba,” Marial told journalists.
The two neighbours agreed late last month to open their border in a bid to foster cooperation and to encourage business.
The two countries fought along their undemarcated frontier in March and April, sparking fears of wider war and leading to a UN Security Council resolution ordering a ceasefire.
It also ordered the settlement of unresolved issues under African Union mediation.
A previous round of talks in early August led to a breakthrough deal on export fees that landlocked Juba will pay to Khartoum to ship its oil through northern pipelines. The details however still need to be finalised.
At independence, South Sudan took with it two-thirds of the region’s oil, though processing and export facilities remained in the North.
In January, the South shut off oil production — damaging the economies of both countries — after accusing Sudan of stealing its oil.
Officials have said that even once a final deal is reached on oil it could then take from three to six months before exports could resume.
The AU set a September 22 deadline for this round of talks after the two sides failed to reach a comprehensive agreement last month, missing a UN deadline of August 2.