A top Sudanese official says people in south Sudan will no longer be citizens of the north if their region votes for independence in a January referendum.
Information Minister Kamal Obeid told state media Saturday that south Sudanese will be considered citizens of another state if they choose independence.
On Friday, southern Sudan President Salva Kiir said northern authorities have not made unity an attractive option, and that all signs point to a secession vote.
Sudan's January 9 referendum will allow residents of the country's semi-autonomous south to choose whether or not to become an independent country.
At the United Nations Friday, leaders of north and south Sudan vowed to work for peace as U.S. President Barack Obama called for an on-time referendum in Sudan.
President Obama told a high-level U.N. meeting the stakes for the January referendum are enormous and said the fate of millions of people lies in the balance.
U.N. Secretary-General Ban Ki-moon, who hosted the meeting on the sidelines of the U.N. General Assembly, said the referendum must be peaceful and free of intimidation.
The referendum grew out of the Comprehensive Peace Agreement in 2005 that ended two decades of civil war between northern and southern Sudan.
Preparations for the voting, including delineation of a prospective north-south border, are far behind schedule.
Some information for this report was provided by AFP and Reuters.