Sainsbury has begun testing shoppers’ attitude to square-shaped cans with its own label tomato soup the first product to be trialled at its Reading store.

The retailer said that it can fit 20% more square cans on its shelves and it would also transport around less fresh air.

The new tins have a pull-back lid, solving the problem of how to open them with a standard tin-opener.

Both the round and square versions will be available in-store for 39p each to gauge which shoppers prefer.