Although he said that "nothing illegal" had happened, the book payment posed, he said, "a moral-ethical problem".
Tesco admitted that it had overstated its profits because it had incorrectly booked payments from suppliers.
Last month, Tesco drafted in Deloitte to comb through its books after a whistleblower identified an issue with the way the retailer booked payments from suppliers.
The problem relates to when the retailer books payments received from suppliers who pay the big grocery chains to run in-store promotions on their behalf.
Tesco's shares have nosedived since the retailer admitted last month that a whistleblower had identified an issue with the way it booked payments from suppliers.
Diamond Foods said Wednesday it would restate earnings for the last two years and replace its top two executives after the board found the company had booked payments to walnut growers in the wrong periods.
In February, for example, Ms. Nichols was one of two JDN executives on a conference call to analysts in which she emphasized that Mr. Nichols, her husband, did not seem to have benefited personally from the off-the-books payments.
At JDN, management experts said, a more independent board may not have been able to prevent the off-the-books payments, but it probably would have responded more forcefully once the scandal broke.
If American multinationals made off-the-books payments directly to Chinese reporters, editors or producers, rather than simply buying space or air time through media agencies, the American companies could be at risk of violating the United States Foreign Corrupt Practices Act.
The SFO launched a criminal investigation into accounting practices at Tesco in October 2014 after the company admitted it had overstated profits by £263m because it had incorrectly booked payments from suppliers, relating to issues such as marketing costs or reaching sales targets.
The SFO kicked off a criminal investigation into accounting practices at Tesco in October 2014 after the company admitted that it had overstated profits by £263m because it had incorrectly booked payments from suppliers, for reasons such as marketing costs or reaching sales target.
