Sir Richard Branson, who owns 72 per cent of the company through Virgin Group, had backed NTL's tentative 323p-a-share offer. But Virgin Mobile's board rejected the deal on the grounds that it undervalued the business.
Virgin Group's representative on the Virgin Mobile board, Gordon McCallum, absented himself from the decision to reject NTL's bid.
With the Christmas period out of the way the market is now expecting NTL to make a formal offer. But rises in the share prices of both companies could affect the structure of any deal, which was originally made as an all-paper offer.
NTL retains Buchanan Communications while Finsbury advises Virgin Mobile.