US retailer Limited Brands has confirmed that it is investigating a series of allegations of child labour on farms in Burkina Faso that grow Fairtrade and organic cotton used in its Victoria's Secret apparel.

The company said that after it learned of the allegation it began working with internal stakeholders to fully investigate the matter.

"Depending on the findings, we are prepared to take swift action to prevent the illegal use of child labour in the fields where we source Fairtrade-certified organic cotton in Burkina Faso," the company said in a statement.

The statement follows a Bloomberg report which describes the life of a 13-year-old-girl who is beaten by the farmer she works for on a cotton field in Burkina Faso. The cotton picked by the girl went to factories in other countries where it was made into Victoria's Secret underwear, the report said.

The report notes that the lucrative premiums paid for organic and fair trade cotton have "perversely - created fresh incentives for exploitation". The programme has attracted subsistence farmers who say they don't have the resources to grow fair trade cotton without forcing other people's children into their fields, "violating a key principle of the movement".

Limited Brands established a pilot programme to purchase Fairtrade-certified organic cotton, mainly from women farmers in Burkina Faso, back in 2007. "We were committed to this initiative because of its potential to generate life-changing opportunities for some of the world's poorest women," it said.

Swiss NGO Helvetas and certification body Fairtrade International, who were both mentioned in the article, also say they are conducting full and immediate investigations into the matter.

"We take this allegation on the violation of human rights of the child very seriously and have put in place appropriate actions," a statement from Fairtrade International said. But it added it is not yet able to confirm whether the child labour cases are on Fairtrade certified farms.

"UNPCB is the national organisation for cotton farmers in Burkina Faso comprising hundreds of thousands of farmers, of which only a fraction belong to Fairtrade certified community-level cooperatives," it noted.

While Fairtrade prohibits child labour as defined by the International Labour Organization (ILO) minimum age and the Worst Forms of Child Labour conventions, "no person or product certification system can provide a 100% guarantee that a product is free of child labour," the group says.

It adds that "simply paying more for cotton is not enough to ensure children are not abused, neglected and/or exploited."

"Fairtrade provides a rigorous certification and audit system designed to detect and remediate cases of child labour. We guarantee that if breaches of our requirements on child labour are found, we take immediate action to protect children, prevent the farms using child labour from selling into the Fairtrade system, and then support the producer organisation to strengthen its own systems and develop child protection policies and procedures adapted to their specific context."

The body, which coordinates Fairtrade labelling and sets Fairtrade standards around the world, adds that while "this important human rights issue" is prevalent in West Africa and in cotton production more generally it is concerned the allegations may discourage companies from sourcing cotton from Burkina Faso or other impoverished areas.

This which would have a devastating negative impact on cotton producing communities and their families, including girls and boys," it explains.