Yemenis search for survivors in the rubble of houses destroyed by Saudi-led air strikes in a village near Sanaa. Photo / AP
Fighting and air strikes have destroyed airports and blocked supplies of food.
The fighting in Yemen threatens to cause widespread hunger and thirst and displace huge numbers of people, creating another humanitarian disaster in a region already reeling from the crisis in Syria, according to analysts and aid workers.
The impoverished Arabian Peninsula nation of 25 million was struggling with alarming malnutrition levels even before an offensive by Shiite Houthi rebels prompted a military intervention last month by a coalition led by Saudi Arabia.
Now, the coalition's air strikes, as well as the fighting at Yemen's airports and seaports, are impeding access to food and other supplies.
According to the United Nations and humanitarian aid agencies, major urban centres, including the southern city of Aden, which has a population of about one million, may run out of drinking water.
The fighting has displaced thousands of Yemenis, and a continuation of the unrest could produce waves of refugees reminiscent of the flight of Syrians from cities and towns engulfed in that country's civil war, analysts and aid workers say. About four million people have poured out of Syria and six million more are internally displaced because of the fighting.
Looking to exploit Yemen's chaos are extremist groups such as al-Qaeda in the Arabian Peninsula and Isis (Islamic State), according to Fawaz A. Gerges, professor of Middle Eastern politics at the London School of Economics.
"If Yemen descends into all-out war, which is a likely scenario, we could witness a greater humanitarian crisis than that of Syria, in terms of refugees and mass starvation," he said. "You could end up with al-Qaeda being the main winner after this conflict."
The Houthi rebels have seized vast tracts of Yemeni territory and in February toppled the US-backed Government of President Abed Rabbo Mansour Hadi. The Saudi-led coalition, which has conducted air attacks against the Houthis and threatened a ground assault, hopes to restore Hadi to power. The embattled President fled Yemen last month for Saudi Arabia, which views the Houthis as proxies of Shiite Iran.
Sitara Jabeen, a Geneva spokeswoman for the International Committee of the Red Cross, said that on Sunday, the Saudi-led coalition gave the organisation permission to fly two planes to Yemen carrying aid workers and 48 tonnes of medical supplies. But the Red Cross had not yet been able to charter aircraft that would travel to the war-torn country, she said.
Adel al-Jubeir, Saudi Arabia's ambassador to the United States, said, "We are engaging with international relief organisations to facilitate the provision of aid." But he indicated that delivery of supplies by plane was unlikely, because Saudi air strikes had destroyed runways and "pretty much shut off Yemeni airports".
The UN estimates more than 500 people have been killed in the fighting in the past two weeks. Meanwhile, supplies of food, fuel and water are dwindling, and government services such as healthcare are deteriorating rapidly.
Julien Harneis, the Yemen representative for Unicef, said shrinking supplies of fuel were threatening the ability of towns to run ambulance services and of hospitals to refrigerate vaccines.
In addition, the lack of diesel fuel means pumps cannot draw well water for the chronically parched country. For years, experts have warned that Sanaa could be the first capital in the world to run out of water.
Already, intense fighting in Aden has stopped the pumps, depriving most of the city of drinking water.
The city also is struggling with prolonged power cuts.
Grant Pritchard, Oxfam's director in Yemen, expressed concern about "a humanitarian disaster on our hands in the coming weeks and months" if the fighting does not stop.
Most international aid workers have left the country because of the danger, and their organisations have had to scale back operations. Foreign businesses such as oil companies have suspended work, while money from abroad - a crucial source of help for millions of Yemenis - has stopped flowing.
The country's meltdown has left many of the nearly two million Yemenis working next door in Saudi Arabia desperate to send cash but blocked by a breakdown in the system of exchange used to transfer currency to Yemen.
Supermarket shelves are increasingly bare. According to some estimates, Yemen imports more than 90 per cent of its food.
Even if food were arriving unimpeded from abroad, though, transporting it inside Yemen had become increasingly difficult because of fighting and air strikes, said Abdul-Ghani al-Iryani, a Yemeni political analyst.
That had caused a spurt in prices of basic goods in rural areas by as much as a third, a huge burden in a country where nearly half the population lives on US$2 ($2.64) a day or less, Iryani said.
"If the situation deteriorates further, it will be a full-blown famine."
This has added to his concerns about a refugee crisis that could compel masses of people to seek safety beyond Yemen's borders. There are unconfirmed reports that Yemenis have begun fleeing across the Gulf of Aden to Somalia.
Yemen
25m population 16m rely on aid 10m do not get enough food 13m lack access to clean water