The Competition Commission's long-awaited remedies report on its two-year investigation to ensure better competition in the country's 120 billion pound grocery market could be released on Friday.
A Commission spokesman said the report, which had been expected on Thursday, was not yet ready to be published.
He said it could be out on Friday but did not rule out its release slipping into next week.
The decision is being closely watched by the largest supermarket groups Tesco, Asda, J. Sainsbury and WM Morrison Supermarkets that stand to be most affected by any changes to the system.
The Commission has said it could consider introducing an ombudsman to adjudicate on issues arising between grocers and suppliers, and may advise changes to planning laws.
In the provisional findings published on October 31, the Commission found there were features of the grocery market that prevented, restricted or distorted competition.
