More than 11 million children in Yemen in acute need of aid: UNICEF

Geert Cappelaere, regional UNICEF director, said in Amman, that the agency had flown 1.9 million doses of vaccines to Yemen on Saturday. He described the shipment as a "very small step" amid the immense demand.

"We hope all will live up to their promises. These supplies are urgently needed," said Gappelaere. "The war in Yemen is sadly a war on children. Yemen is facing the worst humanitarian crisis I have ever seen in my life."

"Two million children today in Yemen suffer acute malnutrition."

The senior UNICEF official added new alarm bells were sounding about the disastrous health condition in Yemen as the outspread outbreak of diphtheria has already spread to five provinces.

Yemen is witnessing one of the world's worst outbreaks of cholera, with nearly one million people infected. Some 2,200 people have died from the disease.

Last week, the International Rescue Committee said the "collective punishment" in Yemen is driving 500 children into malnutrition every week.

Saudi Arabia and its allies intervened in neighbouring Yemen in March 2015 to push back the rebels who control the capital Sanaa, in an attempt to restore the government of Abd Rabbo Mansour Hadi to power.

The UN has listed Yemen as the world's number one humanitarian crisis, with 17 million people in need of food, seven million of whom are at risk of famine.

Since 2014, the war in Yemen has killed at least 10,000 civilians.