Reports on Tuesday suggest that QPR now lead the chase for Hooper's signature after submitted an offer of around £5m for the player.
Celtic are travelling to Belfast for Wednesday's Champions League qualifier against Cliftonville without Hooper.
Bhoys assistant manager Johan Mjallby said Hooper was suffering from a groin strain but also admitted they had received an improved offer from QPR.
Hull and Norwich have both had bids for the forward rejected this year.
The Iron will receive a percentage of the transfer fee.