The European Union on Wednesday denounced what it said was the "brutality" of Sudan's Rapid Support Forces (RSF), which recently captured the key city of El-Fasher.
The statement came as reports emerged of mass atrocities there and the killing of five Red Crescent volunteers in Kordofan.
"Civilians being targeted based on their ethnicity underscore the brutality of the Rapid Support Force," said a statement by the EU's foreign policy chief Kaja Kallas.
"The Rapid Support Forces bear responsibility for protecting civilians in areas under their control, including aid workers, local responders, and journalists," said the statement, co-signed by the EU's commissioner for crisis management, Hadja Lahbib.
"Humanitarian organizations must be granted immediate, safe and unconditional access to all those in need. Civilians wishing to leave the city must be allowed to do so safely."
After an 18-month siege marked by starvation and bombardment, the city is now under the control of the RSF -- descendants of the Janjaweed militias accused of genocide two decades ago.
The paramilitary group, locked in a brutal war with the army since April 2023, launched a final assault on the city in recent days, seizing the army's last positions.
In the neighboring region of North Kordofan, the International Federation of Red Cross and Red Crescent said five Sudanese Red Crescent volunteers had been killed in Bara on Monday, and that three others were missing after the RSF took control of the town on Saturday.
Meanwhile, the UN's World Food Program (WFP) said Wednesday that its two top staff in Sudan had been ordered to leave the war-torn country by the foreign ministry, without explanation.
"This decision to expel WFP's country director and emergency coordinator comes at a pivotal time," it said.
"Humanitarian needs in Sudan have never been greater with more than 24 million people facing acute food insecurity and communities impacted by famine," it added.