“Despite a climate of heightened insecurity and instances of procedural irregularities that removed an important safeguard of the process, South Kordofan’s elections were generally peaceful and credible,” the organization said in a statement.

Incumbent governor Ahmad Harun was announced winner Sunday, beating the province’s deputy governor, Abdelaziz al-Hilu, who dropped out of the race claiming the poll was rigged.

However, the Carter Center, which monitored the electoral process, backed the result.

“Voting, counting and results-aggregation processes were conducted in a non-partisan and transparent manner under intense scrutiny from leading political parties,” the centre of former US president Jimmy Carter said.

Hilu, who is number two in the northern branch of the former rebel Sudan People’s Liberation Movement (SPLM), had run against Harun in the vote that ended on May 4.

Harun, a leading member of the north’s ruling National Congress Party (NCP) is wanted by the International Criminal Court on charges of war crimes committed in Sudan’s western Darfur region.

He received 201,455 votes compared to Hilu’s 194,955 votes, the centre noted, with the NCP winning 33 seats in the legislature to SPLM’s 22 seats.

Analysts warned of potentially explosive consequences of failure in the elections in one of Sudan’s most heavily militarized regions, which also has strong links to the soon-to-be-independent South, from which almost all of the North’s oil is pumped.

Tensions have been running high in the border state, which was a key battleground in the devastating 1983-2005 civil war between the Khartoum government and the rebels.

Former rebels in the south led an independence referendum in January, in which almost 99 percent voted to split from the north, with formal separation due in July.

However, South Kordofan was not included in that referendum and will remain in the North.