Supabarn announced last month it was selling all its supermarkets in Canberra and NSW except Kingston, which was still being developed in partnership with CIC Australia, and Gymea, Sydney.

Coles has eight supermarkets in Canberra and 262 in NSW, and under this deal would own other supermarkets in Canberra's CBD, Kaleen, Wanniassa, Crace and Casey and four in Sydney including Five Dock.

The Australian Competition and Consumer Commission launched a public review of the planned takeover in June.

It is accepting submissions until July 20 on the deal, particularly on the closeness of competition between Coles, Supabarn and other operators and potential impact on grocery prices, specials, product quality, service levels or range of products.

The commission will hold a consumer forum at the QT Canberra Hotel on from 6pm on Monday, August 3.

It is designed for consumers to have their say on the plans and any effect it would have on competition.

Several industry commentators expected the sale would be approved, creating a more level playing field against Woolworths. One commentator said the ACCC didn't have enough power to intervene.

Independent grocery and liquor shops previously said they would ask the watchdog to block the proposed acquisition.

Master Grocers Association chief executive Jos de Bruin said that even though Supabarn was a valued member of the industry group and it had led the independent sector, his organisation would object to the deal to the Australian Competition and Consumer Commission.

Consumers can register for the forum online before Friday, July 24 or make a written submission.

The ACCC is expected to release its decision on the plans in September.