Millions of people in South Sudan are at risk of catastrophic levels of hunger and suffering as the political crisis-hit citizens of the country are not able to return to their homes and plant crops, Oxfam International has warned.

South Sudan's civil war has resulted in thousands of killings and displacement of more than a million people over the past few months. The recently signed agreement between President Salva Kiir and rebel leader Riek Machar is falling apart, diffusing hopes for a quick peace.

Oxfam's Colm Byrne urged the international community to act immediately to help millions of displaced people, who are facing looming hunger and suffering.

Pointing out the looming crisis, Byrne said, "Following the trauma and the hardship that people have endured . our concern is that many of these communities will not have the time and the opportunity to plant crops in order to have food at the traditional harvest time in September/October."

Byrne, Humanitarian Advocacy Manager at the aid organization, stressed that proving the crisis-hit people with seeds and tools for growing crops could help ensure that they do starve.

The aid organization is urging donors to meet the United Nation's funding appeal for South Sudan of around $1.3-billion, which currently has a shortfall of $700 million.