Nearly a fifth of imported chicken products do not correctly state on the packaging how much water has been added, according to a sampling programme carried out by local authorities over the past year.

The figure is up from 13% in 2008/09. The FSA said it did not believe the increase represented a ­significant problem.

The products were tested as part of a targeted sampling programme, and rates of non-compliance were expected to be higher than if the samples had been selected randomly, the FSA added.