Geneva:  One in every three people is suffering from chronic hunger in Yemen where growing food shortages could spark further unrest or mass migration, United Nations aid agencies warned on Tuesday.

Despite widespread hunger, life-saving food rations have been slashed again in the fractious country due to a lack of donor funding, the UN's World Food Programme (WFP) said.

Some 7.2 million people, one third of Yemen's population, suffer from chronic hunger, according to the UN agency. About 3.4 million of them require food aid, but only 475,000 are getting rations it was forced to halve in May.

They include 270,000 people who fled fighting between government forces and rebels in and near the northern town of Sa’ada. Many have sold their last livestock or foregone medical care while waiting to see whether a fragile truce holds.

"People have three other options after that -- revolt, migrate or die. A cut in rations is not a first step, it's a last resort," WFP spokeswoman Emilia Casella told a briefing.

"The rest of the people are receiving no assistance right now. And those who are receiving assistance are getting half of what they ought to be getting," she added.

Bread and tea

More than one in 10 children suffers from acute malnutrition in Yemen, where stunting rates are second only to Afghanistan, Casella said. Yemeni children of over a year old have arrived at WFP feeding centres weighing the same as a newborn child.

"Many families essentially eat only bread and tea."

The remainder of the 500,000 receiving aid include refugees from neighbouring Somalia and Ethiopia, as well as some Yemeni children under five and pregnant or lactating women.

Yemen's government, struggling to stabilise the Arab world's poorest country where al Qaeda is trying to strengthen its foothold, agreed a truce in February with the northern rebels to halt fighting that has raged on and off since 2004 and displaced more than a quarter of a million people.

Cattle farmers who fled fighting in Saada now face a "very serious and dramatic situation", as most have sold their livestock and used what little money they had to pay for rent or food, the UN refugee agency said.

"People are still not going back to their areas of origin. They still feel it is unsafe and fear the mines and unexploded ordnance," said Andrej Mahecic of the UN High Commissioner for Refugees (UNHCR).

"They want to see proof that the peace is holding. So this could not have come at a worse moment for them," he said.

Children are the most vulnerable in food shortages, according to the UN children's fund UNnicef. "They are the first to suffer," said spokeswoman Christiane Berthiaume.

The WFP has received $27.7 million towards its appeal of $103 million for Yemen this year. The United States, Britain, Germany, Italy and Saudi Arabia are among donors so far, but other countries have lagged, according to Casella.