Negotiations between North and South Sudan are to be put on hold until the south's official secession on Saturday, leaders announced on Monday. The move comes as a disappointment to Western countries who were hoping for a quick deal.
Sudan's oil-producing south is due to officially declare independence on Saturday - a split that was voted for in a referendum promised in a 2005 north-south peace deal.
The north and south, which fought a civil war for decades, have yet to agree on the position of their shared border and how they will manage oil revenues.
The north's army and fighters with links to the south have also been clashing in Southern Kordofan, the north's main oil state, in recent days, according to the United Nations.
Western governments have kept up pressure on both sides to resolve at least some of their disputes before the partition, fearing the eruption of another full-blown conflict that could reverberate far beyond Sudan.
South Sudan's president, Salva Kiir, met President Omar Hassan al-Bashir, who will lead only the north after the split, in a conference in Addis Ababa organised by IGAD (the Intergovernmental Authority on Development in Eastern Africa).
"(IGAD) strongly commends President Bashir and ... Salva Kiir for signing the framework agreement for continuing negotiations after July 9, 2011, for the resolution of all outstanding issues in the spirit of the CPA (the 2006 Comprehensive Peace Agreement)," IGAD said in a statement.
It praised both sides for the deals they had made, including an agreement to deploy Ethiopian U.N. peacekeepers in Abyei, a disputed region that has seen north-south fighting.
But it said it was concerned about the lack of progress in other areas, including discussions over splitting debts and how the south will pay the north to transport its oil to Sudan's only sea port, on the north's Red Sea coast.
Khartoum stands to lose about a third of Sudan's total landmass and about three-quarters of its known oil reserves when the south secedes.
Under the terms of the 2005 accord, the north has been receiving half of the revenues from oil drilled in the south. But after the split, the south will own all the oil drilled on its territory.
It will have to pay the north pipeline fees to transport it, but these are likely to come to significantly less than the revenues the north has been receiving until now, with consequences for an economy that has relied heavily on oil.
The south has said Bashir will attend its independence day celebrations in its capital Juba on July 9, a fact that could embarrass any Western dignitaries at the event.
The International Criminal Court has issued warrants for Bashir's arrest to face charges of masterminding war crimes during the Darfur conflict in western Sudan.