The risk of mass starvation in four countries - northeast Nigeria, Somalia, South Sudan and Yemen - is rapidly rising due to drought and conflict, the UN refugee agency said on Tuesday.
"We are raising our alarm level today that the risk of mass deaths from starvation among populations in the Horn of Africa, Yemen and Nigeria is growing," UNHCR spokesman Adrian Edwards told a news briefing.
"We are already seeing a rise of displacement."
Amid a funding shortfall and sharply deteriorating availability of food, a humanitarian crisis possibly worse than that of 2011 when 260,000 people died of famine in the Horn of Africa "is fast becoming an inevitability", he said.