Leeds and Charlton both had the player on trial pre-season and were interested in the former Arsenal trainee, who joined Palace in July 2000.
But they could not compromise on the £750k compensation Palace were demanding for the 23-year-old, who has refused to sign a new contract at Selhurst Park.
The Eagles could now end up out of pocket because Fifa rules allow players under 24 who are out-of-contract to move abroad on a free.