Dennis estimated that the amount Tesco collected from supplier payments rose by £1.7bn over five years to £2.4bn in February 2014 and accounts for 30% of cash profits.
In its report Deloitte concluded that supplier payments had been pulled forward or deferred in a manner that was contrary to Tesco's accounting policies.
"Lots of different businesses flex when they choose to put certain cheques in the bank to hit quarterly targets," said Kantar Retail analyst Bryan Roberts of the supplier payments.
The retailer confirmed a £263m hole in its profits relating to the misbooking of supplier payments, a matter now being investigated by City regulators.
In its report, Deloitte said supplier payments had been "pulled forward or deferred" in a manner that was contrary to Tesco's accounting policies.
Tesco has added thousands of lines to its range in recent years, a phenomenon that has been blamed on supplier payments.
The inquiry has focused on the timing of supplier payments linked to in-store promotions that are often arranged months in advance.
Tesco's poor rating comes despite the attempts of its chief executive, Dave Lewis, to change behaviour at the group after its £263m supplier payments accounting scandal.
(BLOOMBERG NEWS) Lear, a G.M. Parts Supplier, Reports a Subpoena The auto parts supplier Lear Corporation has received a subpoena from the Securities and Exchange Commission seeking information about General Motors's accounting for supplier payments and credits.
Premier and Novation, which say their contracting decisions are untainted by supplier payments, release no public accounting of how much each supplier pays them, or the terms of individual contracts.
