The United Nations on Saturday rejected calls by south Sudan to send peacekeepers and set up a buffer zone along the country's tense north-south border ahead of a southern vote on independence next year.
Sudan's oil-producing south is 66 days away from the scheduled start of a politically sensitive referendum on whether to secede or stay part of Sudan, a vote promised in a 2005 peace deal that ended decades of civil war with the north.
Sudan's Muslim north and its south have still not agreed on the position of their shared border and analysts fear conflict could re-erupt in contested zones, some of which contain oil.
There will not be UN peacekeepers on the buffer zone, it's unrealistic, Alain le Roy, UN undersecretary-general for peacekeeping operations, told journalists shortly after concluding a meeting with representatives from the African Union and several other countries in the Ethiopian capital.
The common borderline is too wide and (it) is not realistic to deploy troops, he added.
Diplomats from the UN and the AU have announced that there will be months of intensive talks starting with a five-day meeting in Khartoum that begins on Sunday aimed at reaching a consensus over the contested oil region of Abyei.
The UN has 10,000 peacekeepers stationed in Sudan, not counting its joint mission with the African Union in the western province of Darfur.
Most of the 10,000 are in the south and in three former civil war battle ground areas along the border. More than 2 million people died during the two-decade long war between Sudan's Islamic north and the south, where most are Christians or follow traditional religions.
Southern officials have accused Khartoum of arming militias to provoke conflict and demonstrate the south cannot govern itself ahead of the 2011 secession poll, scheduled for January 9.
Le Roy however dismissed those claims.
We can't confirm any strong buildup from both sides. They are building up defensive forces - they are on a defensive posture, but we haven't seen any buildup of an aggressive nature from either side.Boulton)