Rescue workers in northern India have brought over 800,000 people to safety following last month's floods.
However, officials believe tens of thousands more are still trapped.
Indian armed forces, other official bodies and aid groups have since used boats to hunt for survivors, some of whom have spent up to two weeks trapped on roofs or isolated high ground without food or clean water.
Rescue operations are continuing, although there have been reports of many people refusing to leave their villages, even though they are waist- or neck-deep in water.
Around 100 people are confirmed to have died in the floods, but the real number is certain to be far higher as many were simply washed away by the deep water and strong currents that swept through rural areas.
Water levels have receded in recent days, allowing aid workers to access more areas and bring more people out
But officials also cautioned that the drop in water levels was likely to be temporary, with the Kosi river likely to hit its peak flow on several weeks towards the end of the monsoon season, at the end of September or beginning of October.
In Nepal, where 50,000 people have also been left homeless, officials say they cannot begin work on repairing the river defences until the monsoon season ends.
Downstream in Bangladesh, 20 of the country's 64 districts have been hit with officials estimating that a quarter of the low-lying delta country's landmass was under water.
Separately, the northeastern Indian state of Assam is also being hit by monsoon flooding of the Brahmaputra river and its tributaries, with up to 1.5m people displaced.
