The country descended into chaos last year after Muslim rebel coalition Séléka seized power, unleashing a wave of killings and looting that in turn sparked revenge attacks by a Christian militia.
John Ging, director of operations for the UN Office for Coordination of Humanitarian Affairs, told a news conference in Geneva yesterday: "It has all the elements that we have seen elsewhere, in places like Rwanda and Bosnia.
"The elements are there, the seeds are there, for a genocide. There's no question about that."
Mr Ging, who recently returned from a five-day trip to the country, said the crisis was foreseen, avoidable and produced by the international community's neglect over many years.
A UN human rights spokesman said earlier this week intercommunal violence had risen to "extraordinary vicious levels" but Mr Ging said it was incorrect to describe the situation as intercommunal violence, although an extremely violent minority were intent on inciting a wider conflict.
He added: "The communities are not in conflict with each other. There are people from each of the communities who are conducting atrocities against people from the other community. And they are doing it in the name of their communities, but they're not representing their communities."
He said the population of 4.5 million was being polarised. In the town of Bossangoa, some of the country's 866,000 displaced people were living in camps within sight of their homes, but were "subsisting in squalor" because they were too scared to go home.
Mr Ging said the country was now little more than a territory on a map, without the infrastructure of a state.
The police force and army have disintegrated, leaving 1600 French and 4000 African Union peacekeepers to try to prevent further outbreaks of violence.