The viability of a £500 million bid for Somerfield has been questioned by reports that John von Spreckelsen, executive chairman of Somerfield, is said to have deliberately undervalued the group's property portfolio by as much as £1 billion.

The net book value of the chain, which is subject of intense take-over speculation, is £542.1m, but that is reportedly based on a valuation in 1996.

Property experts have now said that the freehold and long-leasehold Somerfield and Kwik Save stores is more in the region of £1.4bn, based on conservative estimates. Around two-thirds of the 1,300 stores are thought to fall into that category.

A Somerfield spokesperson said: 'John von Spreckelsen believes that in a turnaround situation you need a tight balance sheet, which means that if anything you are undervalued. There are no plans to revalue the property.' Last week's bid by a consortium headed by John Lovering and Rob Mackenzie would therefore appear significantly short of the mark and will be considered by shareholders in a new light.

A sale at an undervalued price would open the way for the swift sale of part of the group's property to Sainsbury's, M&S, Tesco and Asda. All four are on the look out for stores in the Somerfield size range to roll out their convenience formats.

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