Evidence has emerged raising doubts about the wisdom of last week's decision to refer Morrisons' bid for Safeway to the Competition Commission.
The referral was driven by concern about potential local and national monopolies.
But research from Spa Marketing (see chart) shows that the number of people within two miles of both a Morrisons and a Safeway store is less than 2.2 million.
In contrast, more than 12 million people are within two miles of Sainsbury's and Safeway or Tesco and Safeway. The number within two miles of Asda and Safeway is 6.9 million.
Spa Marketing managing director Dr Mark Shaw said: 'A Morrisons' takeover of Safeway poses no threat to consumer choice. By letting Morrisons into the big league, a takeover might increase competition.'
Morrisons was surprised that Secretary of State for Trade and Industry Patricia Hewitt decided to refer it to the Competition Commission along with the bigger players.
The grocers expect to hear the results of the Commission's deliberations in mid-August.
Fashion tycoon Philip Green was given the go-ahead to put a bid together without reference to the Commission.
He is expected to await Safeway's mid-April trading update before proceeding with any cash offer.