Former Birmingham owners David Sullivan and David Gold have formally submitted an offer for English soccer club West Ham United - but new rivals could emerge for the takeover before the weekend.

Sullivan and Gold have proposed two different offers. 'One,' reports the Guardian newspaper, 'is to buy West Ham outright and assume full control and the other is to purchase a 50% stake that would come with the guarantee of funds for new players. It is believed that would see Gold and Sullivan pay about £21m for a 50% shareholding and the same amount to service the short-term debt and strengthen a threadbare playing squad when the transfer window reopens.'

The newspaper adds: 'There have been reports that Straumur, the largest shareholder in CB Holdings, is seeking close to £80m, suggesting that Sullivan and Gold will come up well short with their bid. Whether that valuation is realistic is debatable. A source close to the club said West Ham owe around £49m to several banks, a further £19m to Sheffield United to be paid over the course of five years as a result of the Carlos Tevez affair and another £15m to clubs to cover outstanding transfer-fee instalments.'

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Straumur has invited other bidders to come forward, with rumours intensifying of a move from the Far East. That would see West Ham become yet another English club with a foreign owner, joining more than half of the league's 20 clubs.

'Should their bid fail, Gold and Sullivan, who are worth an estimated £750m between them, will almost certainly give up on West Ham and turn their attention to alternative options, with League One Charlton Athletic likely to be high on their list,' notes The Guardian.