Child workers, some as young as 10, have been found working in a textile factory in conditions close to slavery to produce clothes that appear destined for Gap Kids, one of the most successful arms of the high street giant.

Speaking to The Observer, the children described long hours of unwaged work, as well as threats and beatings.

The discovery of the children working in filthy conditions in the Shahpur Jat area of Delhi has renewed concerns about the outsourcing by large retail chains of their garment production to India, recognised by the United Nations as the world's capital for child labour.

According to one estimate, more than 20 per cent of India's economy is dependent on children, the equivalent of 55 million youngsters under 14.

With endorsements from celebrities including Madonna, Lenny Kravitz and Sex and the City star Sarah Jessica Parker, Gap has become one of the most successful and iconic brands in fashion.