The Competition and Markets Authority has said the Tesco-Booker deal could pose a threat to independent symbol stores.

The potential damage to symbol retailers forms the basis of the regulator’s decision to move to a more in-depth ‘phase two’ investigation into the deal. The regulator identified 350 local areas where it thinks independent retailers could be harmed by Booker giving them worse deals in order to stunt their businesses.

A statement from the CMA describes this threat, stating: “There is potential for Booker to reduce the wholesale services or terms it offers the symbol stores it currently supplies, in order to drive customers to their local Tesco.”

Tesco denied this was the case. A spokesperson said: “We remain convinced that it will bring benefits for consumers, independent retailers, caterers, small businesses, suppliers and colleagues.”

The CMA said there are more concerns being considered, but did not mention what they are. The new phase two investigation will include exploring these other concerns and seeking further "views and evidence" from the industry.

The current timeline means the findings on the Tesco-Booker deal will be published just before Christmas 2017, within the time frame predicted by Booker Wholesale CEO Charles Wilson earlier this year.