The Blues were relegated from the Premier League last season which has prompted a review of finances at the club.
Hughton tried to get Ranger on loan, but Mike Ashley insists he wants the player off the club's book, and that means cash up front ... cash Brum don't have.
Key players like Roger Johnson, Lee Bowyer and Barry Ferguson have all left the club so far this summer, while Scott Dann and Cameron Jerome continue to be linked with moves to Premier League clubs.
Hughton: "It's important that we have very good footballers at this football club and anybody that goes has a value, they are still Birmingham City players until they are not.
"When I took this job, I was very aware of the consequences of having been relegated and like I said, we have to work around that one."
Ranger is the latest Newcastle player to criticise the club via Twitter after bemoaning his lack of pre-season action.
The 20-year-old striker said: "Most used sub in the prem last season. Now I'm struggling to even get a pre season game. haha.. #laughORcry what a joke.
And for everyone's info. I love this club. Wouldn't want to be anywhere else but got to think about my future."