GENEVA - The United Nations warns Yemen is hanging by a thread as more than five years of war have sapped the country of its energy and destroyed its economy and the well-being of its people. The U.N. and Saudi Arabia are hosting a virtual pledging conference to raise $2.4 billion to assist millions of Yemenis.

U.N. officials describe the situation in Yemen as catastrophic. They say the country sits atop a pile of seemingly insurmountable problems. Years of conflict have killed hundreds of thousands of people, displaced millions and destroyed Yemen's economy and infrastructure.

The U.N. says four out of five people, or 24 million, need lifesaving aid. Ten million are on the verge of famine, and disease is widespread. Added to this mix is COVID-19, the disease caused by the coronavirus.

U.N. Secretary-General Antonio Guterres says Yemen's first case of COVID-19, which was reported on April 10, is spreading rapidly throughout the country.

"The pandemic poses a terrifying threat to some of the most vulnerable people in the world, weakened by years of conflict, and with a health system that is already on the brink of collapse. Since then, reported cases are in the hundreds and are highly likely to be undercounted, since testing rates are some of the lowest in the world. There is every reason to believe that community transmission is already under way across the country," Guterres said.

Guterres says tackling COVID-19 on top of the existing humanitarian emergency requires urgent action and money.

Mark Lowcock, the under-secretary-general for humanitarian affairs and emergency relief coordinator, noted many humanitarian operations in Yemen have run out of money and will soon grind to a halt. He warned more than 30 of 41 major U.N.-supported programs in Yemen will close in the next few weeks without additional funds.

"That means many more people will die. COVID-19 rapid response teams are funded only until the end of June. Next month, we could start winding down treatment for severely malnourished children. Support for cholera facilities will also start to reduce," Lowcock said.

Saudi Minister of State for Foreign Affairs Adel al-Jubeir is calling for a political solution to relieve the suffering of the Yemeni people. He said the Saudi kingdom is Yemen's biggest donor, having contributed more than $16 billion over the past years for humanitarian, developmental and reconstruction aid.

Critics of Saudi Arabia view the generosity with a cynical eye, considering the country's direct involvement in Yemen's devastating war.