(Updates with third defection of a military official)
By Denis Dumo
JUBA, Feb 20 (Reuters) - Parts of war-ravaged South Sudan are suffering famine, a government official said on Monday, adding nearly half the country's population would lack reliable access to affordable food by July.
South Sudan has been mired in civil war since 2013, when President Salva Kiir fired his deputy. Since then the conflict has increasingly split the country along ethnic lines, leading the United Nations to warn of a potential genocide.
The fighting has prevented many farmers from harvesting their crops, and hyperinflation, which reached more than 800 percent last year, has put the price of imported food beyond the reach of many.
Parts of the country have also been hit by drought.
"In greater Unity (state), some counties are classified in famine or ... risk of famine," Isaiah Chol Aruai, chairman of South Sudan's National Bureau of Statistics, told a news conference in Juba.
Aruai said some 4.9 million people were expected to become "food insecure" between February and April, with that number rising to 5.5 million by July.
"Famine has become a tragic reality in parts of South Sudan and our worst fears have been realised," Food and Agriculture Organisation (FAO) South Sudan representative, Serge Tissot, said at the news conference.
The United Nations defines famine as when at least 20 percent of households in an area face extreme food shortages, acute malnutrition rates exceed 30 percent, and two or more people per 10,000 are dying per day.
The fighting has uprooted more than 3 million people and a U.N. report released on Monday said continuing displacement presented "heightened risks of prolonged (food) underproduction into 2018".
South Sudan is rich in oil resources. But, six years after independence from neighbouring Sudan, there are only 200 km (120 miles) of paved roads in a nation the size of Texas. In the fighting, food warehouses have been looted and aid workers killed.
Kiir's government has been hit by high-profile defections. Two top military officials resigned their positions last week, citing ethnic favouritism, human rights abuses and other charges.
Brigadier General Kamila Otwari Aleardo Paul, who had been in charge of logistic support in the military, also resigned on Monday, accusing the government of tribalism.
Lul Ruai Koang, spokesman for the armed forces, said the three defections would not hamper the operations of the military.
"The military is not a one-man show," he told a news conference, adding it was not clear which country in the region the military officials had gone to.
Punishments handed out to some soldiers from the Dinka, Kiir's tribe, for crimes including rape and murder were being set aside, said Colonel Khalid Ono Loki, one of officials who resigned. The minister of labour has also defected to the rebels. (Writing by Elias Biryabarema and Katharine Houreld; Editing by Andrew Roche)
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