Newcastle owner Mike Ashley would consider selling the club if he recouped all the money he has invested during his six years on Tyneside, the Independent has reported.
However, Sports Direct News - Ashley is also the owner of that company - said the Magpies had distanced themselves from talk of a sale and cited a club source as dismissing the speculation. Newcastle declined to comment when approached by the website.
A recent report filed by auditors Deloitte listed the money Ashley would want to recoup as being in the region of £267 million, with a similar figure understood to be what would be needed to buy the club from him.
The news comes after a difficult spell for the club in the wake of the controversial decision to appoint Joe Kinnear as director of football. Earlier this week, Kinnear issued an apology for his recent comments about Newcastle fans.
He had been invited to a supporters' group meeting at the Newcastle Labour club on Monday, but did not attend and a friend instead read out his apology on his behalf.
In a statement, supporters' umbrella group NUFC Fans United urged Ashley, who bought the club from Freddy Shepherd in 2007, to "consider his position".
"This house declares that Mike Ashley is not a fit and proper custodian of a footballing institution that has a proud history and tradition and enjoys one of the biggest and most fervent followings in European football," the statement said.
"We call for Mike Ashley to consider his position as owner of Newcastle United and to begin a process of exiting before he does any more damage to either the club or his own reputation."
In September 2008, Ashley made an unsuccessful attempt to sell the club. Despite a number of potential bidders making themselves known, none was willing to match his asking price, which was then understood to be around £250millon.
The initial cost of the club, £134 million, rose considerably when the accounts revealed a significant level of hidden debt missed when he opted not to undergo due diligence during the purchase process. The club's relegation from the Premier League in 2009 is believed to have cost Newcastle a further £30 million.