Sudan bans UN mediator as conflict ceasefire negotiated

Sudan declared UN envoy Volker Perthes, a key mediator in the country's conflict, persona non grata.
Military leader Gen. Abdel Fattah Burhan demanded Perthes' removal in a letter.
Saudi Arabia and the US brokered a new 24-hour ceasefire between warring factions starting Saturday.
The conflict between Sudan's military and paramilitary forces has killed over 860 civilians and displaced hundreds of thousands.
Aid groups warn of a potential humanitarian crisis without an end to the fighting.