Thousands of people, mostly children, are believed to have died of hunger and malnutrition.
Oxfam's executive director Winnie Byanyima said the region was on the brink of famine. "If action is not taken now, we could see millions of people move into the famine category. So I'm here to push decision-makers to avert a catastrophic loss of life," she said. "I'm not happy about the United Nations and the coordinating role it should play for all of us. We can do better than this. These people deserve better,"