The UN aid chief, Tom Fletcher, held a phone call Monday with Sudan's RSF paramilitary leader, Mohamed Hamdan Dagalo, on hostilities around El-Obeid.

According to a statement from the United Nations Office for the Coordination of Humanitarian Affairs (OCHA), Fletcher stressed the need to maintain safe access for humanitarians to reach those in need, as well as safe movement for civilians.

"They also discussed challenges that are impacting the ability of United Nations and NGO partners to carry out life-saving relief efforts, including bureaucratic impediments," the statement read in part.

Earlier this year, the UN's independent fact-finding mission on Sudan concluded that the siege and capture of El-Fasher bore "the hallmarks of genocide."

This was further corroborated by the UN humanitarian coordinator in Sudan, Denise Brown, who concluded a mission to El-Obeid on Sunday, where she engaged with partners on the aid response and witnessed the impact of attacks on civilians and civilian infrastructure.

Brown said the city had been under "intense drone strikes" by the RSF recently, and "civilian infrastructure is being hit on a regular basis," including water, power and fuel supplies.

A strategic hub in the southern Kordofan region, El-Obeid has been encircled for months by the RSF, the paramilitary group that has been fighting Sudan's army since April 2023.

A city of half a million people that hosts nearly 100,000 refugees displaced by the civil war, El-Obeid has faced its most intense RSF attacks yet in recent weeks.

The UN Human Rights Council on Monday ordered an "urgent inquiry" into violations and abuses in El-Obeid, warning of the looming risk of "large-scale atrocities."