South Sudan faces a "perfect storm" of violence, floods, an economic crisis and hunger, with 79,000 people in Jonglei State facing catastrophic food insecurity, UN humanitarians said on Thursday.

"Overall, more than 7 million people in the country face food insecurity -- an increase of more than 20 percent compared to 2023 at mid-year," the UN Office for the Coordination of Humanitarian Affairs (Ocha) said. It blamed underfunding the humanitarian response and new arrivals due to the conflict in neighboring Sudan as adding to the storm.

"The number of people facing catastrophic conditions -- IPC 5, the highest level -- in parts of Jonglei State in South Sudan is projected to almost double through July -- rising to 79,000 people, compared to 35,000 people at the same time last year," UN Ocha said.

The office said South Sudan is preparing for the worst floods in 60 years. Starting in September, the humanitarian community aims to provide life-saving assistance to 2.4 million of the 3.3 million people expected to be affected by flooding in northern, northeastern and central parts of the country.

UN Ocha said that $264 million would be needed but underfunding of the humanitarian response in South Sudan is an ongoing challenge.

Six months into 2024, this year's appeal for broader response efforts is less than 20 percent funded, with just more than 353 million of the nearly $1.8 billion required.