Juba - Over a third of South Sudanese face starvation as the war-torn nation runs the risk of a full-blown famine, the UN and government said on Wednesday.Despite a peace deal to end civil war, nearly five million people - more than ever before in the world's youngest nation - need food aid to survive."The risk of famine cannot be ruled out," Minster for Agriculture Lam Akol said, a warning backed by the UN.Civil war erupted in South Sudan in December 2013, but rebel chief Riek Machar returned to the capital in April as part of a peace deal which saw him become vice president, forging a unity government with President Salva Kiir.Aid workers have been able to access some of the hardest hit areas since then, but violence continues between multiple militia forces who now pay no heed to either Kiir or Machar."The level of food insecurity this year is unprecedented," the UN Food and Agriculture Organisation (FAO), UN children's agency Unicef and the World Food Programme (WFP) said in a joint statement."Up to 4.8 million people in South Sudan - well over one-third of the population - will be facing severe food shortages over the coming months, and the risk of a hunger catastrophe continues," they added.Akol, reading from a UN-backed specialised hunger assessment called the Integrated Food Security Phase Classification (IPC) report, singled out areas of the Unity and Bahr el Ghazal regions as the hardest hit.MalnutritionConditions in some areas there during the IPC analysis showed indicators within the most severe category, "catastrophe" or "phase five". Famine is declared when those conditions are faced by a fifth of the population, the technical threshold."The levels of malnutrition among children continue to be truly alarming," said Unicef chief in South Sudan Mahimbo Mdoe.In addition, the world's youngest country is struggling to stem soaring inflation caused by the war, rampant corruption and the near collapse of the oil industry upon which the vast percentage of government foreign exchange earnings depend.The government has cancelled celebrations for its fifth anniversary of independence on July 9.Over 100 000 children have been treated for severe malnutrition this year, a 40% increase compared to 2015, and a 150% increase since 2014, Mdoe added.Tens of thousands have died in the civil war and two million forced to flee their homes.All sides have been accused of perpetrating ethnic massacres, recruiting and killing children and carrying out widespread rape, torture and forced displacement of populations to "cleanse" areas of their opponents.