Central African Republic crisis: Rebels reject new Muslim PM Kamoun
He is the first Muslim prime minister in the Christian-dominated country and is to lead a transitional government.
More than half of the population is in urgent need of assistance, the UN says.
An estimated 20% of inhabitants have fled their homes in the conflict which began as Seleka rebels seized power in March 2013.
This gave rise to the creation of largely Christian anti-Balaka militias and the situation descended into ethno-religious violence.
The Seleka leader, Michel Djotodia, stood down as president in January as part of regional efforts to end the fighting.