The UN aid head, Stephen O'Brien warned on Monday of early warning signs of genocide in the Central African Republic after there was renewed violence.
"The early warning signs of genocide are there," Mr O'Brien was quoted by Al Jazeera as saying at a UN meeting.
"We must act now, not pare down the UN's effort, and pray we don't live to regret it."
Mr O'Brien's comments came following a recent visit to the country.
Calling for an increased peacekeeping presence, he said now was the time for the MINUSCA peacekeeping force to "deliver on its critical protection mandate".