Nearly 80% of Yemeni children need immediate humanitarian assistance amid the collapse of the country's health system in the face of the two-year-long civil war, three UN agencies have said.
Two million Yemeni children are malnourished, making them vulnerable to cholera, the heads of the World Health Organisation, Unicef and the World Food Programme said in a joint statement.
Yemen is facing the world's worst cholera outbreak in years.
The agencies called on the international community to intensify its support for the Yemenis.
A two-year Saudi-led campaign against Yemen's Shiite Houthi rebels has damaged infrastructure and caused medicine shortages in the Arab world's poorest country.
The war has killed more than 10,000 civilians, displaced three million people and pushed Yemen to the brink of famine.