The Federation of Small Businesses (FSB) is urging the Competition Commission to adopt a tough stance in its investigation into the behaviour of supermarkets.

As part of its investigation, the commission is considering a number of alleged abuses, which the FSB believes could threaten the existence of independent retailers.

According to the FSB, many small to medium-sized enterprises (SME) are scared to voice their concerns.

A number of Britain's supermarkets face potential allegations in areas such as the procurement of land banks and the treatment of suppliers, in addition to selling items below cost.

"Independent retailers cannot compete for goods if supermarkets sell them to the public at lower prices than independent retailers can buy from wholesalers," said Clive Davenport, trade and industry chairman for the FSB.

"No stone should be left unturned and offenders should be brought to book," he added.

The Competition Commission is expected to publish its findings and recommendations in November 2007.

The FSB is a UK-based lobby group for Britain's SMEs.