"The Secretary General is appalled by reports that dozens of children and other civilians have been killed in the latest deadly attacks in South Kordofan," spokesman Stephane Dujarric said in a statement, Anadolu Agency reported.
Three separate drone strikes were reported in the town of Kalogi on Dec. 4, with two hitting a kindergarten and another striking a hospital where the wounded were receiving treatment, according to the statement.
Guterres condemned all assaults on civilians and civilian infrastructure, warning that targeting educational and medical facilities may constitute breaches of international humanitarian law.
The same day in North Kordofan, an aerial attack struck a humanitarian convoy carrying food aid to North Darfur, damaging a World Food Program truck and critically wounding the driver.
"The Secretary-General deplores this further attack on humanitarian operations at a time of dire needs," the statement said.
Guterres urged all nations with influence over the warring parties to act immediately and use their leverage to force an immediate cessation of hostilities and halt weapons shipments fueling the conflict.
He insisted that all parties comply with their obligations under international law across all conflict zones in Sudan.
The civil war between the Sudanese army and paramilitary Rapid Support Forces (RSF), which began in April 2023, has killed thousands and displaced millions.