The number of people living in slums in India has more than doubled in the past two decades and now exceeds the entire population of Britain, the Indian Government has announced.

India’s slum-dwelling population had risen from 27.9 million in 1981 to 61.8 million in 2001, when the last census was done, Kumari Selja, the Minister for Housing and Urban Poverty Alleviation, said.

The figure is the latest illustration of how India’s recent economic boom has left behind millions of the country’s poorest people, raising fears that social unrest could undermine further growth.

India’s economy has grown by an average of 8 per cent annually over the past four years, and yet a quarter of its population of 1.1 billion still lives on less than $1 (50p) a day.

The expansion of India’s slums is partly due to the rise in India’s total population, which increased from 683 million in 1981 to 1.03 billion in 2001.

That has been exacerbated by mass migration from the countryside as millions of farmers have forsaken the diminishing returns of small-scale agriculture to seek the relatively high wages of manual labourers in India’s cities.

But the ballooning slum population is also evidence of the Government’s failure to build enough housing and other basic infrastructure for its urban poor, many of whom live without electricity, gas or running water.

India’s largest slum population is in Bombay, the country’s financial and film capital, where an estimated 6.5 million people – at least half the city’s residents – live in tiny makeshift shacks surrounded by open sewers. Bombay is also home to Dharavi, Asia’s biggest single slum, which is estimated to house more than a million people.

Delhi, the national capital, has the country’s second-largest slum population, totalling about 1.8 million people, followed by Calcutta with about 1.5 million.

Mrs Selja says that it will cost India four trillion rupees (£49 billion) to build the estimated 24 million housing units needed to accommodate India’s slum-dwellers. She has called for the Government and the private sector to address the problem jointly and has launched several schemes to provide basic public services to slum-dwellers. But civil rights activists accuse the Government of willfully neglecting India’s slums, while favouring commercial property developers who often bribe local officials and fund politicians’ election campaigns.

“The rise in slums is due to the lack of affordable housing provided by the Government,” said Maju Varghese, of YUVA Urban, a nongovernmental organisation that has been working with the urban poor for more than 20 years. “The Government has withdrawn from the whole area of housing and land prices have gone to such heights that people can’t afford proper housing,” he said.

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