Food manufacturers who fail to cut salt levels by as much as their rivals are to be asked why this is the case by the Food Standards Agency.

The agency is in the process of comparing salt levels in foods with targets agreed with the industry in March 2006. It wants to find out which products in individual categories remain high in salt, but also identify companies whose products are high in salt compared with similar products on the market.

Where companies have missed targets or are under-performing their peers, they will be asked by the FSA for an explanation.

The move is part of FSA plans to review the targets themselves and establish whether any need to be increased as it seeks to cut consumption to an average of 6g per person per day by 2010. The review will go out to consultation in the

summer.