The defender would be a welcome addition to any squad in the Championship - Sunderland, Crystal Palace and Mick McCarthy's Wolves are among the potential suitors.
"There are five clubs actually talking to myself about Tony," said Holloway.
"I have made him the best offer we can and, at the minute, I have turned down one offer because I don't believe it's good enough.
"If the clubs don't match my valuation, and Tony knows what that is, then he will be re-signing for us."
"The clubs know exactly what we would accept to get a very good left-back from us," added Holloway.
"I have to be very careful what I say, but I believe a player of his class and quality should not be able to leave my company on a free transfer.
"If he was 23 we could get some compensation for him, but we can't.
"From my position I find it very annoying. He has helped us and we have helped him and, all of a sudden, someone else can take him in three or four months time.
"I know you could say everybody is in the same boat, but I don't feel that is fair."