Sainsbury's and Harrods have been caught out selling farmed fish as wild by an FSA survey that has uncovered widespread inaccuracies in the labelling of seafood.

Analysis of fish labelled as 'wild salmon' at both retailers showed the product was actually farmed. Many fish lines in other major stores were incorrectly labelled.

An Asda in Gloucester sold farmed sea bream without mentioning its origin.

Sea bass was another commonly mis-sold species.

The FSA found 30% of fish on sale had the wrong information on the label. This was the case for 75% of the fish in fishmongers and for 10% from the multiples. Although technically illegal, the problems mainly related to minor errors, such as a fishmonger describing mackerel as Cornish. The regulations require origin to be described as 'north-east Atlantic'.