Yemen's stocks of fuel and vaccines will run out in a month unless a Saudi-led military coalition allows aid into the blockaded port of Hodeidah and Sanaa airport, UNICEF's representative in the country said on Friday.
Meritxell Relano, speaking by phone to reporters in Geneva, said fuel prices had risen 60 percent and there were urgent concerns about a diphtheria outbreak, as well as food shortages because of the port closure.
"The situation that was already catastrophic is just getting worse," she said. "The impact of this is unimaginable in terms of health and diseases."
After two years of civil war, Yemen has 7 million people on the brink of famine and has had 900,000 suspected cholera cases in the past six months.
The number of new cases has fallen consistently for the past eight weeks, according to data from the World Health Organization.
But progress against cholera, which has killed 2,196 people, could be reversed by the blockade, WHO spokeswoman Fadela Chaib told a regular U.N. briefing in Geneva.
"If the closure is not stopped in the coming days, we may see that the progress is stopped," Chaib said. "We can see even more cases and more deaths as a result of not being able to get access to people."
The closure of Hodeidah port prevented a ship setting sail from Djibouti with 250 tonnes of WHO medical supplies on Wednesday. Trauma kits in particular are running short.
"If the hostilities continue and the ports remain closed, we will not be able to perform life-saving surgeries or provide basic healthcare," Chaib said.