It is cheaper to buy a child than a buffalo in India, according to activists who marched on a summit of South Asian nations in Delhi yesterday to protest against human trafficking.

Most end up in bonded labour or working as prostitutes, the leaders of Bachpan Bachao Andolan (Save the Childhood Movement) said as they escorted more than 200 children to the gates of the Indian Parliament to call for changes to legislation.

“While buffaloes may cost up to 15,000 rupees (£177), children are sold at prices between 500 and 2,000 rupees,” Bhuvan Ribhu, who conducted a study to be released later this year, said.

Their demonstration coincided with the two-day annual meeting of the South Asian Association of Regional Cooperation attended by the heads of government for Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan and Sri Lanka.

Police prevented the demonstrators from reaching the meeting hall but allowed them to present a petition to the office of Manmohan Singh, the Prime Minister.

Activists maintain that the association’s convention for preventing trafficking in women and children has failed to stem the problem because its definitions cover prostitution but not forced labour.

They claim that more than 50,000 Nepalese children and 40,000 Bangladeshi children are bought and sold across the border every year by scouts rounding up workers for farms, carpet factories, quarries and brothels.

Desperately poor parents frequently exchange their children for money, often as little as $5. Some falsely believe that their children are being taken to work as domestic servants and will send money home. Few ever return. Others trade their sons and daughters to pay money lenders. Up to 15 million children in India, most of them from low-caste families, could be enslaved to work off someone else’s debt, according to a Save the Children report published last month on the 200th anniversary of the abolition of slavery by Britain. The report also said that children account for a fifth of India’s workforce in sandstone quarries and nearly a third of sex workers.

In October India introduced a law banning children under 14 from working as domestic servants or in the food and hospitality sector. Offenders face two years in prison.

India still has more than 12.6 million child workers aged 5 to 14. In Asia the estimated number is 122 million, according to the International Labour Organisation. India still has more than 12.6 million child workers aged 5 to 14, the largest number of any country in the world. Campaigners say that the new law has yet to make any difference because India’s economic boom creates an insatiable demand in the cities for cheap labour. In Asia the estimated number of child workers is 122 million, according to the ILO.

Poor families send their children to work as soon as they are physically able. Social workers in Rajasthan this month asked the state government to consider extending its subsidised lunch programme beyond 10 years old to the age of 16 to reduce drop-out rates. Most child labourers are school drop-outs.

Trade unions in India are also being urged to press their members not to employ child labourers.

Bachpan Bachao Andolan and other nongovernment organisations last month completed a 3,100 mile (5,000km) march from Calcutta to Delhi to raise awareness about illegal child labour. About 100 rescued children joined the march.

Activists complain that police officers are bribed by traffickers to turn a blind eye to their activities or help to move people around the country.

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