A tribe residing in a disputed border region claimed by both Sudan and South Sudan held a unilateral vote Sunday to decide which country to join.
The three-day vote in the oil-rich Abyei region was not sanctioned by either government, and it was unclear early Monday whether the outcome would be accepted by either side.
Neither country has been able to decide who should vote in the Abyei referendum, a standoff that has delayed the vote for months.
The Khartoum government has demanded the Sudan-allied minority Misseriya nomads vote alongside the majority Ngok Dinka, while the Juba government wants polling limited to its Ngok Dinka allies.
The Associated Press quoted vote organizers Sunday as saying they expected up to 100,000 Ngok Dinka people to cast ballots, despite warnings from the African Union that the unsanctioned voting would increase the risk of violence between the two tribes.
South Sudan President Salva Kiir and his Sudanese counterpart Omar al-Bashir met last week in Juba, where they agreed to work on fully re-opening their two countries' shared border, which was closed after fighting last year.
The two countries also have had disputes over oil, which is pumped from the south but must pass through the north to reach international markets.