Sudan's defense minister warned on Tuesday that a referendum on southern independence could be delayed if the country's north and south cannot resolve issues such as borders, sharing oil revenues and who is eligible to vote.
Southern Sudan is scheduled to vote Jan. 9 on whether it will split from the north and become an independent state.
The referendum is part of a 2005 peace agreement that ended a 21-year civil war between the mostly Muslim north and predominantly animist and Christian south. The agreement also set up a unity government in the capital, Khartoum, and an autonomous government in the south to rule until the referendum.
Nearly 2 million people died in the civil war, one of the world's bloodiest of the second half of the 20th century. That war is separate from the conflict in Darfur, a western Sudanese region where fighting since 2003 has left up to 300,000 people dead and forced 2.7 million to flee their homes, according to U.N. figures.
North-south tensions have mounted as the referendum nears. How the sides navigate the vote could determine whether Sudan _ Africa's largest country _ returns to civil war.
Defense Minister Gen. Abdul-Rahim Hussein on Tuesday reiterated warnings, which have already been issued by other northern officials, that the referendum could be delayed.
"Referendum should lead to peace because it is not the goal in itself but a means to an end," Hussein told reporters after meeting in Cairo with Egyptian President Hosni Mubarak. He said if the key issues remain unresolved, "logic and reality" suggest the referendum be delayed.
Hussein said the vote must be based on clearly defined borders. He said 20 percent of the north-south boundary has not been decided yet, including the border in the region of Abyei that is home to oil fields worth millions of dollars.
Residents of Abyei are to vote on the same day in their own separate referendum on whether to remain with the north or join the south. Both southern tribes and semi-nomadic Arabs with ties to the north share Abyei.
Southern Sudanese leaders reject any talk of delaying the vote and say they will hold the referendum unilaterally if the north doesn't cooperate.
Southern Sudanese President Salva Kiir said earlier this month that any delay would cause a return to violence "on a massive scale." He also asked members of the U.N. Security Council to deploy U.N. peacekeepers along the border to ease tensions as the vote nears.
Hussein, the defense minister, warned that a unilateral declaration of independence by the south would be "illegal."