The controversial referendum to decide whether Sudan should be split in north and south is just three months away.

Tension is already brewing along the border as the UN says it has confirmed that president of south Sudan had asked for a buffer zone to be created, fearing a military build-up in the area. The request has been labelled illegal by a senior Sudanese official if it goes ahead without the central government's approval.

As Al Jazeera's Haru Mutasa reports from Juba, southern Sudan's capital, there is also the contested Abeyi region that will have a separate vote to decide whether the region should join the north or south is also stirring trouble.

Despite calls from the north to delay the process, leaders from Abeyi threaten to hold a referendum on their own. Leaders from both the north and south will meet later this month to resume talks on Abeyi. If they cannot agree on a way forward, some here in the south fear the oil-rich region of Abeyi could thrust Sudan back to war.