The U.N. Security Council warned Saturday of an "imminent risk of mass atrocities" in Sudan and called on paramilitary forces surrounding the city of el-Obeid to halt their advance amid escalating concerns over civilian safety.

"The members of the Security Council expressed concern about the imminent risk of mass atrocities and demanded the RSF immediately halt its assault on el-Obeid," the Security Council said in a statement.

Council members also called on the parties to the conflict to immediately halt the fighting.

The city, in the Kordofan region, has been besieged for several months by the Rapid Support Forces (RSF), at war with the regular army since April 2023.

The U.N. voiced fears of a repeat of atrocities in el-Fasher, where an October 2024 assault bore "hallmarks of genocide."

The U.N. said Friday that Pekka Haavisto, the secretary-general's special envoy for Sudan, called Mohamed Hamdan Daglo, chief of the rebel paramilitary forces, to urge him not to attack el-Obeid.

Haavisto "underscored the need to urgently de-escalate the situation in el-Obeid and avoid any actions that may worsen the already dire humanitarian situation and put civilian lives at risk," said Stephane Dujarric, spokesman for U.N. Secretary-General Antonio Guterres.

Dujarric said aid workers were "preparing for the potential movements of large numbers of people" fleeing the city, adding that humanitarian colleagues were "getting ready for the worst while hoping for the best."

Dujarric also said Haavisto spoke with countries with influence over the warring parties to encourage dialogue and prevent the assault.

The conflict in Sudan has killed tens of thousands of people and displaced more than 11 million, creating what the U.N. describes as the world's largest humanitarian crises.