Retail leaders fear Home Office plans to create holding cells for criminals in shopping centres could land store staff with the task of "babysitting" prisoners.
A Home Office consultation on the Review of the Police and Criminal Evidence Act 1984 includes proposals to use short-term holding facilities in retail malls for the detention of offenders for crimes such as shoplifting.
The British Retail Consortium said it believed the scheme could help the fight against soaring retail crime - but warned that
the responsibility for apprehending and holding criminals must not shift to shop staff.
BRC director general Kevin Hawkins said: "Cells in retail centres should never be used for the long-term detention of criminals, and shop staff should never be called on to fulfil the role of the police."
A Home Office spokesman said suspects would be held under the supervision of a police officer, and never for more than four hours.