The United Nations’ special envoy to Sudan says he is stepping down from the role, three months after Sudan’s military junta declared him persona non grata — something that’s not allowed under the U.N. Charter. Volker Perthes testified to the U.N. Security Council on Monday.

Volker Perthes: “At least 5,000 people have been killed since the start of the conflict and over 12,000 injured. And these are conservative figures. The actual number is likely much higher. … What started as a conflict between two military formations could be morphing into a full-scale civil war.”

Some 20 million people in Sudan — nearly half the population — face acute food insecurity. Six million are just one step away from famine. On Monday, leaders of over 50 international human rights and humanitarian groups accused global leaders of failing to take action in the face of atrocities in Sudan.