The company is controlled by the Tchenguiz Family Trust, which holds the majority of the family's wealth. The loss was for the period up until the end of May 2009 and compares with the £32.5 million in the previous year.
The FT report said Rotch has incurred big losses from provisions made against amounts due from related companies.
Robert Tchenguiz was particularly hit hard by the credit crisis, losing a huge part of his fortune as a result of exposure to the collapsed Icelandic bank Kaupthing.
His brother Vincent Tchenguiz has been less hit by the downturn, although the losses at Rotch will hurt both brothers' business interests.
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