Italian Massimo Cellino has emerged as a fourth potential bidder for West Ham, BBC Radio 5 Live understands.Cellino, the president of Serie A side Cagliari, where Hammers boss Gianfranco Zola ended his playing career, is thought to be plotting a takeover bid. [LNB]Ex-Birmingham owners David Gold and David Sullivan, finance company Intermarket and the Lotus F1 team boss Tony Fernandes are also in the hunt. [LNB]Cellino is in London and was sighted at QPR's home match on Tuesday night. [LNB]It is understood West Ham will not engage in any activity in the January transfer window until the takeover situation is resolved. [LNB]Sources close to the east London club have indicated a deal could be completed by the end of the week, but it is still not clear who might be favourites to seal a successful deal. [LNB]All four interested parties claim to have connections with the Upton Park outfit, and it could be the £100m asking price is reached. [LNB]Gold and Sullivan say they are long-standing Hammers fans and would make money available for Zola to spend on transfers. [LNB]Intermarket, which was hit by the death at the weekend of chief executive officer Jim Bowe, is believed to have former West Ham striker Tony Cottee as an adviser but must prove it has the funds to secure a deal. [LNB]Air Asia founder Fernandes, who is thought to have been flying into the UK from Malaysia on Wednesday, has been a regular at home matches for many years. [LNB]And Cellino has made no secret of his admiration for former Italian international Zola. "He left football with the same class he had on the pitch," said Cellino after the striker retired from playing. [LNB]The club are currently owned by CB Holding, which has indicated West Ham are £38m in debt. [LNB]The main shareholder in CB Holding is Icelandic bank Straumur, which has previously said it is in no hurry to sell the club although that was before the various bidders became known. [LNB]Zola has insisted he will not have to sell his star players in the January transfer window. [LNB]England goalkeeper Robert Green, defender Matthew Upson and Carlton Cole have all been linked with interest from big clubs.