"I condemn the reported use of women and children as human shields in Kadugli, the hindrance of humanitarian aid and the deprivation of liberty of civilians, including children," says Nkweta-Salami in a statement.
Fighting broke out last week between Sudan's military and the rebel group SPLM-N in the two states of South Kordofan and an-Nil al-Azraq (Blue Nile). Nkweta-Salami warns that the states are "on the brink of catastrophe".
Fighting is also ongoing in the capital Khartoum. Sudan's military advanced in the central parts of the city on Thursday, and is approaching the presidential palace controlled by the paramilitary group Rapid Support Forces (RSF).
The military, which has been at war with RSF since 2023, has carried out an offensive in recent weeks to regain full control over the capital.