The ongoing conflict and related economic downturn in South Sudan has left 3.8 million people facing emergency and crisis levels of food insecurity, according to a new Integrated Food Security Phase Classification (IPC) report, FAO said on Friday.

It warned that unless action is taken, the situation is set to further deteriorate with around 4.6 million people, or some 40 percent of the country's population becoming severely food insecure by July 2015.

The IPC estimates for April, indicate that most of the people affected - 3 million at Crisis level and 800 000 at the Emergency level - are located in the three states of the country's northeastern Greater Upper Nile region hardest hit by the fighting. Many others are from the western part of the Greater Bahr el Ghazal region where conditions have deteriorated as a result of a spillover from the conflict.

The IPC is a multi-partner initiative that uses a standardized approach to classifying food insecurity, particularly in crises situations. Estimates are based on a technical consensus among the involved stakeholders, including governments.