The City Ground outfit have signed six players this summer ahead of their return to the Premier League for the first time in 23 years.
Forest tactician Cooper is pushing to sign more as he looks to build a squad that will be able to survive in the top flight next season.
Garner impressed on loan at Nottingham Forest last season and the club have been looking at the possibility of taking him back to the City Ground,
And it has been claimed that Cooper is still hopeful that an opportunity will come for Nottingham Forest to sign the Manchester United midfielder this summer.
Garner is currently in Australia with the Manchester United squad where Erik ten Hag is looking at his group during pre-season.
The Dutchman wants to closely look at the midfielder before taking a call on his future at the club ahead of the 2022/23 campaign.
Manchester United are likely to want to loan him out again this summer if the manager does not find a place for him in the squad.
Nottingham Forest only have two Premier League loan slots in their squad and they used one up on signing Dean Henderson from Manchester United earlier in the summer.
