Celtic forward Shaun Maloney has called off contract talks until January, according to the club's chief executive Peter Lawwell.
The Scotland player is out of contract at the end of the season and will be free to talk to other clubs in January with a view to signing a pre-contract agreement.
Former Hoops boss Martin O'Neill is likely to try to bring him to Aston Villa while Tottenham have also been linked with a move for the SPFA Player of the Year.
Lawwell said: "Despite making serious and persistent efforts to continue negotiations, Shaun's representatives have indicated they wish to suspend discussions until January when Shaun will have the opportunity to look at options.
"It would seem the reason for this is not financial.
"This development is worrying. However, it should be clearly stated that Celtic are very keen to bring this matter to a successful conclusion.
"That would be one which sees Shaun extend his contract with the club."