Retailers face one of their thorniest dilemmas since ramping up commitments to ethical trading – reconciling human rights with the livelihoods of some of the world’s poorest people.

Top store groups, including Tesco, Marks & Spencer and H&M, have banned the use of cotton from Uzbekistan – one of the biggest producers – following concern that children there were being forced out of school to help with the crop’s harvest.

However, the effects of the decision are being felt in Bangladesh, one of the world’s poorest countries, which imports 65 per cent of its cotton from Uzbekistan. Bangladeshi clothing suppliers fear that the need to import higher-priced cotton from elsewhere might make them uncompetitive.

Store chiefs believe that cotton can be sourced competitively from countries other than Uzbekistan, but acknowledge that in the event of cotton price rises, they face difficult choices.

Bangladeshi suppliers might be expected to shoulder some of any cost rise, but retailers’ ethical commitments would mean they could not be expected to bear the entire burden.

Retailers would have to decide to what extent they would absorb a rise and to what extent it would be passed on to shoppers. “Those are the sort of things being discussed,” confirmed one retail corporate responsibility chief.

A Tesco spokesman said the switch away from Uzbek cotton would be “commercially manageable” and an M&S spokeswoman insisted it would work with suppliers to smooth the transition.

This week, Debenhams became the latest retailer to act on the issue. Uzbekistan has been on the retailer’s banned country list for more than a year, but chief executive Rob Templeman has written to suppliers reiterating its position.

Debenhams head of corporate responsibility Dave Winsor was optimistic that cotton price rises could be avoided.

He said: “If all Uzbek cotton was taken out of the marketplace there could be an impact, but the information we have is that alternative cotton is available at a lesser cost.”

Tesco, H&M and M&S alone account for US$700 million (£357.2 million) of clothing orders from Bangladesh.