Supermarket giant Tesco was rapped after breaking planning rules on how much space it can use for non-grocery products at its Shrewsbury superstore.

A residents group claimed the breach at the Tesco Extra store in Battlefield Road had dealt a blow to town businesses struggling to survive the economic downturn.

The chain has had to apply to vary a condition of its planning permission to allow it to stock 152 sq metres more “comparison goods” – including clothing, DIY, household and recreational goods – at the store after admitting the blunder.

In a letter to Shropshire Council, Helen Attewell, of Tesco’s agent DPP, said the store was keeping to the amount of space allocated in total for sales but she admitted it was using too much of the supermarket for “comparison goods”.

She said: “Since the store commenced trading in April 2007, Tesco has inadvertently been in ‘breach’ of the comparison goods sales restriction.”

She said it meant Tesco had allocated more space on its shop floor to non-grocery goods than it was allowed.

The store had accounted for health and beauty products “which consumers increasingly expect to purchase as part of their main food shop” in its allocation for “convenience goods”, but they should have been classed as “comparison goods”.

Dr Alan Shrank, of Shrewsbury Town Centre Residents Association, is objecting to the new application.

He said: “The retail trade is going through an economic crisis with more empty shops in Shrewsbury than there have ever been and some of that is due to Tesco being in breach of its planning consent.”

Tesco spokesman Felix Gummer disputed whether the variation had affected the town centre.