The Scotland international has been attracting interest from Europa League runners up Arsenal in the summer transfer window.
The Gunners are reported to have made an offer for Tierney but the north London side fell short of Celtic’s valuation of the full-back.
Celtic are thought to be looking for a transfer fee in the region of £22m for their home grown talent after developing Tierney into a promising defender.
Neil Lennon is thought to be close to signing a replacement for Tierney in the shape of Boli Bolingoli-Mbombo to open the door for the Scotland international to move to Arsenal.
However, Allan Preston – who is part of the Stellar Group that represents Tierney – has revealed that Arsenal and other potential suitors will need to meet the “correct value” to convince Celtic to sell.
“It is all down to Celtic – if they get a price that they believe is the correct value for Kieran Tierney he could possibly be on his way,” Preston told BBC Sport, as quoted by Metro. “No one has hit that price yet.
“I know Kieran really well, I had some food with him the other day.
“He is such an unassuming young man. He is wealthy at the moment but he doesn’t possess a watch because he isn’t into material things like this.
“He still hangs about with his pals from when he was a youngster, he sponsors his local pub team where his pals play and he’s not into his designer gear or anything like that.
“As the guys say, he loves Celtic. He absolutely loves Celtic. Will there be a time for Kieran Tierney to go? I think that there will be.
“If it’s just now it will be up to the clubs that are involved – Arsenal, Napoli or whoever – to then put the money on the table and make Celtic think about this.
“If there is a time for Kieran to go it will be up to Celtic, Peter Lawwell and the board.”
Arsenal manager Unai Emery is looking to improve his squad this summer after a disappointing end to the Premier League season.
The Gunners finished in fifth spot in the Premier League table after ending up behind Chelsea FC and Tottenham Hotspur in the top-four race.
The north London side suffered the disappointment of losing 4-1 to bitter rivals Chelsea FC in the Europa League final.
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