South Sudan is standing "on the brink of catastrophe" according to several leading humanitarian charities working in the region.

With food supplies dangerously low, and a shortfall of money to keep humanitarian operations going, fears that a full-scale famine will soon grip the country – which today celebrates its third anniversary – have increased.

Tearfund reports that almost four million people across the war-torn young nation are in desperate need of food, and this figure is expected to rise to at least seven million in the next month. The number of malnourished children is at its highest in five years, having increased by around 300 per cent in the past 12 months.

Despite the emergency effort of multiple relief agencies, the UN's South Sudan Crisis Response Plan published in June warned that a staggering $1.1 billion is still needed "to save lives, prevent famine and avert the loss of a generation of South Sudanese children".

"Famine looms in parts of the country, as the conflict rages on and at a time when rains render some areas virtually inaccessible as roads become rivers of mud. We must prevent the crisis of today becoming a catastrophe tomorrow," Kathleen Rutledge, Tearfund's country director in South Sudan, cautions.

"The World Food Programme has estimated that more than 50,000 children will die this year due to hunger unless there is an immediate and widespread response."

Several other agencies have joined Tearfund's call, in a joint statement released by Oxfam today which warns that: "The risk of famine is rising as the number of people requiring help is steadily rising, but the money to enable agencies to do something about this is not coming through".

"There is a desperate need for peace in South Sudan so that people can go home, go back to school, plant crops and patch their lives back together," the statement reads.

"International pressure is needed on all parties to the conflict to end the violence and to build a nation for all South Sudanese people. However, without more funding now, that future is slipping further away and may not exist for many."

The charities – which include Oxfam, Tearfund, World Vision, Care International, International Rescue Committee, Save the Children and Christian Aid – are thus calling on the public to donate generously to their campaigns, while also demanding urgent intervention from international governments.

"We will be staring into the abyss and fail to avert a famine if funds do not start arriving soon," says Chief Executive of Oxfam Mark Goldring.

"This is a not a crisis caused by drought or flood. It is a political crisis turned violent. The people of South Sudan can only put their lives back together once the fighting ends.

"In the meantime civilians caught up in this crisis not of their making need our help. We are asking the public to help us with our urgent humanitarian work, but mainly we are calling on governments to fund the aid effort before it is too late."

Aimee Ansari, Care International's country director in South Sudan who has witnessed the death of children as a result of critical malnutrition, describes it as "a brutal demonstration of the impact both of the insecurity and the lack of funding". International Rescue Committee's country director Wendy Taeuber added that the situation is putting women in particular in danger: "Worsening food insecurity is placing women and girls at serious risks of sexual violence, exploitation and abuse," she said.

"If we wait any longer, I fear all hope will be lost." Save the Children's Pete Walsh also warned.

Today, July 9, marks the 3^rd anniversary of South Sudan since its secession from the north in 2011 following two bloody civil wars.

Significant political unrest has plagued the world's newest nation ever since, and a fresh wave of violence began on 15December last year in Juba as a result of an attempted coup by soldiers loyal to President Salva Kiir's former deputy Riek Machar. The fighting subsequently escalated, spreading throughout the country and fracturing it along ethnic lines.

Described as "the most pressing humanitarian crisis in Arica", the latest UN reports indicate that at least 1.5 million people have been displaced and five million South Sudanese civilians are currently in need of critical humanitarian assistance.

"What South Sudan needs most is for the global leaders and everyday citizens to press for peace and stability among the decision makers in the country and to provide food and water as quickly as possible to help minimise the loss of life in the days to come," Tearfund's Rutledge insists.