Film star Emma Thompson has urged Tesco to ensure its South African suppliers respect laws about working conditions and pay.
Thompson, who recently visited women workers at a fruit farm in Stellenbosch with Action Aid charity, said suppliers of the supermarket giant were being exploited.
The star of Howard’s End and Sense and Sensibility told the BBC: "They work in a big shed, and they stand for 11 hours. There's a little break but there's nowhere to sit. They're paid 38p an hour, are casual labourers and unfortunately come back year after year for this labour.”
Thompson said there was good legislation in place to protect workers but that it was not being adhered to.
"What Tesco could be doing very usefully is to make sure all the farms that it imports from adhere to a very strict set of regulations. This is not a call for any kind of boycott but is a wake-up call to be responsible about the people that you employ,” she said.
A spokesman for Tesco’s, the UK’s biggest retailer and the largest importer of South African fruit, said it understood it had a responsibility and that it was fully engaged with suppliers, NGOs and charities to improve things.
"We believe that Tesco is not the problem here, it's part of the solution," he said.
"While we don't employ anyone directly, we do know we can help to improve standards of these women and their families."