Sunderland chief executive Martin Bain says David Moyes' side have a "very limited" January transfer budget, with the Premier League club up for sale.
Sam Allardyce's Black Cats spent big a year ago - bringing in Lamine Kone, Wahbi Khazri and Jan Kirchhoff - to beat the drop by two points ahead of rivals Newcastle United.
However, Sunderland are struggling again under Moyes, and are bottom of the pile heading into the midweek fixtures despite further signings - including midfielder Didier Ndong for a club-record fee.
And Bain is adamant the club cannot afford to splash out again next month to retain their top-flight status.
"In terms of this transfer window in January, we have reached a point where there has to be a time where you don't have that short-term hit to plug the holes in the dam," he said.
"At the same time, I'm not saying that Ellis Short is disappearing off into the horizon and is completely closing the purse strings - he is not.
"But the word I've got for you is 'limited' - I could probably say 'very limited' - with regards to the January transfer window.
"The club, in recent years, has reached a point where we can't keep having this short-term fix because it just keeps coming back full circle.
"We are not going to be able to spend to get out of trouble. There will be people who will argue that we did that last year and it worked. I recognise that, but that kind of purchase from the past can lead you to where the club is now.
"That is the loud and clear message - we cannot spend to get out of trouble."
Bain also confirmed that owner Ellis Short is willing to listen to offers for the club he bought in 2009.
"If there is a buoyant housing marking and someone comes up garden path saying they are interested in buying your house, you're going to have a chat with them to see what they are going to say," he continued.
"You're not going to lead them straight back down the path. That is the position at the moment - we would listen to offers.
"But I believe Ellis has the interests of the club at heart and he wouldn't turn away anything that is beneficial to Sunderland Football Club.
"He currently covers the shortfalls and that has to be remembered and applauded.
"I'm confident he will continue to fund the club. It would be a misconception to think Ellis isn't putting money into the club."
