Juba, Oct 19 (IANS): Devastating flooding caused by heavy rains pounding several parts of South Sudan has affected more than one million people.

The UN Office for the Coordination of Humanitarian Affairs (OCHA), in an update released in Juba, the capital of South Sudan, on Friday evening that the floods have so far displaced about 271,000 people in 42 of the country's 78 counties.

The UN agency said that 40 per cent of the affected population is from Northern Bahr el Ghazal and Unity states. It has predicted that the unprecedented floods could affect up to 3.3 million people between September and December.

It said that heavy rainfall and flooding have rendered 15 key supply routes impassable, restricting physical access, Xinhua news agency reported.

South Sudan is facing unprecedented flooding, with forecasts predicting above-average rainfall, river flows from Uganda, and potentially record-breaking floods, according to the OCHA.

The country is one of the 18 hunger hotspots globally where food security is deteriorating, according to UN reports.