Financier Amanda Staveley has submitted a formal £300m takeover offer to Newcastle owner Mike Ashley to buy the club.
Sky News has learnt that Ms Staveley's PCP Capital Partners tabled a bid to buy Newcastle from Mr Ashley late last week.
It was unclear on Monday evening whether PCP was the only credible bidder for the club, although people close to the process said the logical next step would be to award Ms Staveley a period of exclusivity within which to negotiate a deal.
That could come as soon as this week, according to insiders.