Stewart, who was previously finance director at Marks & Spencer, will now join the Tesco board as chief financial officer with effect from 23 September 2014, rather than the previously announced date of 1 December 2014.

As the investigation is underway with Big Four firm Deloitte reviewing the accounts, incumbent auditor PwC said in a statement that it ‘did not comment on client audits for reasons of confidentiality’.

An accounting expert told Accountancy that it sounded like a ‘classic cut off type issue, trying to get income into earlier periods and costs into later ones.

'It is the profits guidance that has been overstated. It looks as if they have noticed the problem when checking things for the more detailed interim statement'.