Fans of the goji berry could soon find themselves unable to buy the fruit as food-safety watchdogs prepare to ban it.

Retailers have already been told to wind down their stocks of products containing the small, red berry and not reorder.

The FSA admits there is no immediate threat to human health, but says it has no choice but to ban goji berries as a novel food under EU legislation, unless retailers can prove they sold the berries before May 1997.

Given that only Chinese food shops stocked the

berries until their recent surge in popularity, most vendors are unlikely to be able to do this.

Once branded as a novel food, goji berries will rank alongside other novel foods such as GM crops or cloned meat. They cannot be sold again until they have been through a rigorous testing regime to prove they are not unsafe to eat. That can take as long as two years, some claim.

The FSA says it has been forced to act after receiving enquiries from a supplier on the legality of gojis. They can be labelled a novel food even though they have been eaten in Asia for centuries.

They have recently been endorsed by TV nutritionist Gillian McKeith and Tesco launched a range of products containing the

berries last year, including cereal bars and dried fruit mixes.

"It's just a berry, so why are they trying to make it into a novel food," said Lesley Cutts, general manager of Goodness Direct.

The market had grown five-fold from almost nothing at the end of 2005, she claimed.

In a sign the FSA is gearing up for the ban, the agency has advised local authorities on how to enforce it and has asked them to take account of the goji's low risk to human health

Vendors have until 23 March to supply evidence. Evidence can be submitted to the FSA at novelfoods@foodstandards.gsi.gov.uk.