Sudan's military on Sunday claimed it repelled a rebel attack on the edge of a region where the insurgents carried out a surprise strike last weekend.
"The armed forces repulses attack of the Revolutionary Front on Um Berembita area," Sawarmi Khaled Saad, the Sudanese army spokesman, was quoted as saying by the official SUNA news agency.
Um Berembita is in the far north of South Kordofan state, near Abu Kershola which the rebel Sudan People's Liberation Movement-North (SPLM-N) says it has controlled since last Saturday.
The insurgents said they had no confirmed information about Um Berembita.
SPLM-N is part of the Sudan Revolutionary Front (SRF) rebel coalition which on Saturday took control of Abu Kershola during coordinated attacks on several nearby areas, including Umm Rawaba, the second-largest town in North Kordofan state.
Unlike Darfur to its west and South Kordofan state, North Kordofan had been generally peaceful.
The SRF said they attacked as part of their strategy to reach the capital Khartoum and overthrow the 24-year regime of President Omar al-Bashir.
The international community widely denounced the rebel action, and Khartoum called it an act of "terrorists".