A representative for Birmingham City Council has told just-food that, although there is no strict timetable, the investigation into the salmonella contamination of Cadbury chocolate products at its factory on the outskirts of Birmingham "is likely to be competed in weeks rather than months." The council's findings will help determine whether legal action will follow.

Cadbury Schweppes was forced to recall more than one million chocolate bars six weeks ago because of low level salmonella contamination caused by a leaking water pipe at its Marlbrook plant.

If the investigation finds that Cadbury was at fault during the salmonella outbreak and subsequent recall, the council could decide to pursue legal action and this could end in a hefty fine for the Birmingham-based confectioner.

"As the home authority for Cadbury we'd ultimately be the people who the company are accountable to," the local authority said. "Until the investigation is completed we aren't going to speculate on what action will be taken," the spokesperson added, confirming that legal proceedings were an option.

Cadbury is also facing the possibility of civil suits filed by people infected with the rare strain of salmonella found at Cadbury. During the five-month period when infected chocolate bars were on sale to the public, a total of 37 people are known to have become ill with the rare salmonella Montevideo strain.

Cadbury has said that the cost of the crisis will total GBP25m.

The Food Standards Agency is also looking at why Cadbury failed to alert the body until five months after the problem has been detected in January.