Celtic chairman Brian Quinn has insisted midfielder Roy Keane will have to accept a substantial cut in wages if he wants to join the SPL leaders.
Roy Keane has talked about playing for Celtic
The 34-year-old, a free agent after leaving Manchester United on Friday, has attracted early interest from Wigan, Bolton and Portsmouth.
Keane has previously said he would like to end his career at Celtic, but at United he earned about £90,000 a week.
Quinn told Radio Five Live: "That's a sum that's out of the question for us."
The Celtic chairman revealed he and manager Gordon Strachan had not discussed as yet whether the Glasgow club would want to sign Keane.
Quinn said: "Would he fit into Gordon's plans? The team is playing very well at the moment and they look settled.
"You wonder whether you would want interrupt things, but that's up to Gordon.
"The other question to consider is the business side.
"We would have to wait and see what Roy Keane is proposing, if indeed he's looking for anything at all from Celtic.
"When he first talked about leaving United as far as I can see the word Celtic didn't pass his lips."
Keane officially left Old Trafford by mutual consent, although reports claim it was a result of a bust-up with manager Alex Ferguson.
Whichever club Keane joins he will not be able to make his debut for them until 1 January.
Although Keane's United contract was cancelled "by mutual consent", Fifa rules stipulate that no player subject to such a move would be allowed to sign for a new club outside the next available transfer window.