Retailers Wal-Mart, Tesco, Carrefour and Metro say they have secured across-the-board workplace standards for employees, to tackle possible labour problems that could arise in global supply chains.

Led by CIES, an international association of food retailers and suppliers, the supermarket chains have been working with Swiss retailer Migros to develop a draft code of standards called the Global Social Compliance Programme, reported The Financial Times.

The code includes standards taken from existing codes of ethics. It also details plans to  standardise differing monitoring initiatives in order to prevent 'audit fatigue'.

However, proposals have been met with a cautious response from some labour rights groups.

Labour Behind the Label spokesperson Martin Hearson told just-style: "We think the programme is not really necessary. All the work they are talking about in the fashion sector is already out there, through the ETI (Ethical Trading Initiative) and JO-IN (Joint Initiative on Corporate Accountability and Workers Rights).

"The corporate effort adds nothing to the process but takes away accountability from the retailers. It is a talking shop more than anything else, and deflects criticism from people like us."