Business groups have criticised plans to publish retailers' food hygiene scores on the internet.

The FSA-backed initiative, Scores on Doors, is set to be launched in London next April with star ratings from zero to five to indicate retailers' compliance with hygiene rules. If successful the scheme may be rolled out across the UK.

But Andrew Opie, BRC director of food policy, said it could be misleading. "The public aren't clued up on this. You may get a retailer getting two stars, which means compliance with the law, but the public may not understand and may prefer one with five stars."

A spokesman for the ACS said: "The five-star system seems incredibly complex and unfair."

Sharon Smith, London, regional policy officer for the Chartered Institute of Environmental Health, which is leading the project, said: "This process will enable us to target resources at those businesses that are having trouble complying and probably do a disservice to the rest of the industry.

"We know everyone has bad days but what the initiative looks at isn't just the bad day. There are issues that will indicate whether the place is well managed or not. If the place is really bad and is closed down, it will be rated again when all the work is done."