In the early 1990s, the parcels sector of British Rail was seeking a fleet of multiple units that would be more cost-effective to run than the locomotive hauled stock it was using. The initial proposal was to convert a number of redundant Class 307 units that were in the process of being withdrawn from passenger service into Class 300 parcels units. Owing to the age of these units however, it was subsequently decided to procure a fleet of new trains. These units, which were ordered in 1994, were initially given the TOPS classification Class 350, before being changed to Class 325.