Tesco has said that “several” staff have been suspended as its new chief executive launches an investigation into its finances. The move follows the announcement that the group had overstated its six-month profit forecasts by £250 million.

The group said that it was working to establish how much impact this would have on its full year results.

Tesco has asked Deloitte to undertake an “independent and comprehensive” review of these issues, working closely with Freshfields, the group's external legal advisers.

Dave Lewis, group CEO, said: "We have uncovered a serious issue and have responded accordingly. The chairman and I have acted quickly to establish a comprehensive independent investigation. The board, my colleagues, our customers and I expect Tesco to operate with integrity and transparency and we will take decisive action as the results of the investigation become clear."