Geneva, Aug 18 (IANS): A humanitarian crisis is unfolding across large areas in South Asia, with more than 16 million people affected by floods in Nepal, Bangladesh and India, the International Federation of Red Cross and Red Crescent Societies (IFRC) said on Friday.

According to the agency, flood levels have already reached record highs in Bangladesh, and water of major rivers such as Jamuna has surpassed warning levels set in 1988, the deadliest flood in the country, Xinhua news agency reported.

"This is fast becoming one of the most serious humanitarian crises this region has seen in many years and urgent action is needed to meet the growing needs of millions of people affected by these floods," an IFRC statement said, citing its staff for Asia Pacific region.

According to the statement, more than one-third of Bangladesh and Nepal have been flooded, and the humanitarian crisis could get worse in the days and weeks ahead.

Many areas in Nepal remain cut off after the floods and landslides, and many villages and communities are stranded without food, water and electricity, it said.

"This tragic flooding in Nepal has claimed at least 128 lives and 33 people are still missing," Dev Ratna Dhakhwa, Secretary General of the Nepal Red Cross Society, said.

The IFRC said over 3.9 million people were affected by the rising waters, and the situation was likely to get worse as swollen rivers from India poured into the low-lying and densely populated areas in Bangladesh.

According to the agency, over 11 million people have been affected by floods in four states across northern India.

The India Meteorological Department has forecast heavy rains in the region in the coming days.