The heavy rains and flooding have affected nearly 30 million people and killed around 2,200 across India, Bangladesh and Nepal since the start of the monsoon in June.

"The toll is 1,668," in India said S.S. Singh, from the national disaster management division in the country's home ministry.

Twenty-one new deaths were reported in the state of Bihar by Saturday afternoon, he added, but the figure does not include some flood-related deaths such as capsized boats last week that claimed dozens of lives.

Some 15 million people were affected by flood waters in northern India, with the worst-off losing their homes and crops, officials have said.

Approximately 1.1 million hectares (2.7 million acres) of farmland were swamped with water, mainly in the northern belt of Bihar.

Almost seven million people were displaced in India's Uttar Pradesh and Assam, but many of these have now returned home.

In Bihar, many roads were still submerged Sunday, including a major highway connecting the state to India's northeast, the Press Trust of India news agency said.

The impoverished state's chief minister, Nitish Kumar, left for the capital New Delhi to press the prime minister for 800 million dollars in aid to restore Bihar's battered farms and infrastructure, the Press Trust of India news agency said.

International organisations and foreign governments from Saudi Arabia to Canada have offered tens of millions of dollars in aid, mainly for Nepal and Bangladesh, where some 40 percent of the land was submerged this year.

In Bangladesh, the toll since June rose to 411, officials said Sunday, as flood victims at makeshift relief camps worried about food supplies.

One 55-year-old woman, who used the name Lily, camped out with her family at a courthouse in a northwestern town and prepared a meal Sunday from three tiny onions, some chillies, a little oil and a few kilogrammes of rice and lentils.

It will be all they eat until her son, a rickshaw puller, can earn again.

"We eat only when he manages some money," said Lily, adding that the rice, pulses and oil came in an aid packet delivered by government officials.

Tens of thousands of people have been admitted to hospital this month with diarrhoea and other water-borne diseases, Habiba Khatun of the Bangladeshi health department said Sunday.

In Nepal, where 99 people died and 300,000 people were affected by the floods, government officials said the first priority was to prevent a disease epidemic.

"We are in high alert regarding epidemic breakout from water-borne diseases in the flood- and landslide-affected districts," said Ishwar Regmi, a home ministry official.