The Barclays bought the home-shopping company from Argos Retail Group as part of an unconditional offer. This means that if the deal does not get cleared by the commission, they will have to find another buyer for it.
The successful takeover of GUS would allow the brothers to merge it with their Littlewoods catalogue business, which they bought for £750m last year and folded into their wholly owned March UK business.
The GUS home-shopping business generated £1.67bn in sales and operating profits of £35m for the year to March 31. It employs 17,500 staff.
The GUS mail order businesses with operations in the UK, Ireland and Sweden includes the Choice and Great Universal Stores catalogues and the Reality logistics and customer care division.
The acquisition was handed over to the competition regulator yesterday following a report by the Office of Fair Trading, which was concerned that the combined company would be more than three times the size of its next largest competitor.
However, the Barclays are reported to be confident that they have a good case for the purchase.
The brothers are currently plotting a global expansion of The Business, which is part of their Press Holdings newspaper operation.
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