Rafa Benitez has warned Newcastle owner Mike Ashley that he must spend money in January if he wants to protect the value of a takeover deal.
Ashley and financier Amanda Staveley met for the first time in London this week to discuss her bid to buy the club.
Sportsmail understand that no agreement was reached during their dinner at a curry house in Hampstead and the offer from Staveley and PCP Capital Partners remains at £250million.
Ashley is holding out for £300m and has claimed that a rival bidder is prepared to pay £320m, although no details are known of the second party.
Another complicating factor is Newcastle’s performance on the pitch and the threat of relegation from the Premier League.
They have taken one point from the last six matches and have slipped to 15th in the table ahead of Saturday evening’s visit of Leicester City.
Benitez is desperate to reinforce a squad he believes was left short after the summer transfer window and has called on Ashley to invest, reminding him that a club heading for the Championship will not be as valuable to prospective buyers.
‘At any football club in the world, the value depends on the first team,’ said the Spaniard.
‘You can talk about everything around (the club) and that’s fine, but if you are in the Premier League and doing well it is easier (to sell).
‘If you are in the Championship it has less value. That is so simple. I think he (Ashley) is a businessman. A businessman will have a clear idea about what he needs to do.
‘It is very simple. You have to be sure that your team is strong enough to stay in the Premier League.’
Benitez thought he had a transfer budget of £70m in the summer but just £40m was spent on players.