New CAR interim president Catherine Samba-Panza has named Andre Nzapayeke as prime minister.
The CAR's new interim leader has ordered troops in Bangui to shoot troublemakers "at point blank range" in a bid to end months of violence.
Michel Djotodia will step down at a summit of regional leaders amid frustration at his failure to quell religious violence in the country.
Violence in the Central African Republic has uprooted nearly a million people, a fifth of the population, and is hampering aid efforts.
More than 100 000 people displaced by religious violence in Central African Republic are in urgent need of basic supplies at the Bangui airport camp.
Dozens were killed in Central African Republic when Ugandan rebels attacked villagers but were then ambushed by Ugandan soldiers, a witness said.