A new general took command of the Sudan Armed Forces (SAF) on Tuesday after what analysts called humiliating attacks by anti-government rebels.
In a ceremony at military headquarters General Mustafa Osman Obeid Salim received an armed forces flag from his predecessor, Ismat Abdul-Rahman, to mark his appointment as chief of staff, an AFP photographer said.
The army, air force, military intelligence and other key commands also changed their top leadership in a shuffle which official media called routine.
A regional political expert told AFP the SAF normally rotates its commanders every three years in May but this year's change was delayed because of fighting at Abu Kershola, South Kordofan.
The military took one month to recapture Abu Kershola and its garrison from rebels of the Sudan Revolutionary Front (SRF), an alliance of insurgents from Sudan's Darfur, South Kordofan and Blue Nile.
Rebels have been fighting for two years in the states of South Kordofan and Blue Nile, while a decade-long insurgency continues in Sudan's far-west Darfur region.
"SAF has a lot of difficulties" to push back the rebels, the regional expert said, asking for anonymity.
The rebel alliance seized Abu Kershola during a coordinated attack on several areas including the strategic and previously peaceful town of Umm Rawaba in North Kordofan.
"This is highly embarrassing" for the authorities, another analyst said.
President Omar al-Bashir, Defence Minister Abdelrahim Mohammed Hussein and South Kordofan governor Ahmed Haroun attended Tuesday's ceremony.
"They say that they are injecting new blood... in order to win the war against the rebels," the regional expert said.
The reshuffle also follows what the government said was a coup plot against it last November.
In April Bashir pardoned about 15 military men and security agents who had been jailed for their roles in the plot.
Analysts say the case, linked to Islamist officers who had once firmly backed the regime, reflects a political struggle within Bashir's government.
Officials have never revealed more than vague details about the conspiracy.
In changing the military leadership Bashir "would like to
be sure of their loyalty and professionalism," the regional expert said.