Czech investor EPH, led by Daniel Kretinsky, views the deal Metro is expected to sign with Germany's Redos group as unfavourable, the source said.

Real's retail properties as well as its operating business were being offered too cheaply, the source added.

Metro and Redos earlier this month agreed a framework under which Real would be sold at a valuation of roughly 1 billion euros (£878.1 million), with Metro initially retaining a 24.9 percent stake in the operating business and a 'put' option to sell that holding which could be exercised after three years.

The liabilities of the struggling chain will be assumed by the new owner, resulting in a preliminary cash inflow of around 500 million euros to Metro.

A spokesman for EPH declined to comment.

(Reporting by Matthias Inverardi; Writing by Arno Schuetze; Editing by Kathrin Jones and Thomas Seythal)