Waitrose has rebuffed criticism over its ethical sourcing policy after it emerged that the UK retailer buys some produce grown in territories occupied by Israel on the West Bank.

Campaigners have said they are concerned that the upmarket retailer could be selling produce grown in occupied areas without clear labelling to indicate the origin of the goods.

Oxfam said that it is fearful that Palestinians are being exploited in the production of goods.

"We are concerned that goods grown there should be properly labelled so that consumers can make an informed choice," a spokesperson for the charity said.

Waitrose sells a selection of herbs grown on six Israeli-managed farms in the West Bank. However, the company emphasised that on these farms the mixed Palestinian and Israeli workforce have "worked side-by-side for many years".

"Waitrose has a policy of full traceability in our supply chain, and high standards of worker welfare and agri-environmental sustainability are essential for any farm supplying us," a spokesperson for Waitrose told just-food.

"Our buyers and food technologists have been to the West Bank recently to see first hand farms supplying our stores and to meet managers and workers. They are fully confident the farms meet our high standards."

The spokesperson added that Waitrose's Responsible Sourcing Code of Practice has established the group's expectations on labour standards, environmental issues and animal welfare.

"We monitor compliance to these standards, and in addition to this, our supplier audits farms at least once a year, examining factors such as worker hours, salaries and employment contracts," the spokesperson added.