The cable giant had requested bids to be submitted by 8 August but it is now expected to name a new deadline next week.
However, according to reports the delay should not prove too much of a problem for Virgin because the sale process is at such an early stage.
Virgin Media was put up for sale earlier this summer after receiving a £5.5bn takeover bid from private-equity firm Carlyle Group.
A $32-$33 per share proposal from Carlyle triggered a formal auction of the company. Other companies linked with bids include providence and European cable operator Liberty Global.
Virgin Media is hoping to raise £11bn through the auction.