Newcastle striker Craig Bellamy is undergoing a medical at Blackburn.
The Welsh striker is at Ewood Park looking to complete a move, with the fee set to be just under £5m.
Bellamy fell out of favour with Newcastle manager Graeme Souness and was told that he had no future at St James Park.
He spent the second half of last season on loan at Celtic and they along with Everton were also interested in signing the 25-year-old.
Newcastle chairman Freddy Shepherd said Celtic had done everything they could to complete a deal.
“I can assure Celtic fans that their club did everything within its power to try and get the player,” he told the club’s official website.
“But it seems the lure of the Premiership is obviously too much.”