Nathan Tyson has confirmed he has turned down a new deal at the City Ground.
As revealed by skysports.com earlier this month Tyson has snubbed the club's offer of a contract extension.
The former Reading and Wycombe hit-man has warned Forest that he could see out the final year of his contract and leave for nothing next summer.
"I was offered a contract and it was not worth signing. It was not what I wanted," Tyson told the Nottingham Evening Post.
"They have said that I have to prove myself and I will - then get a better offer.
"As far as I am concerned, I have a year left on my contract...which means we have a whole year left to talk about it.
Warning"I am keen to stay but, at the end of the day, if the season starts and I am not playing, I might as well look at leaving on a free when my contract expires. I'll be honest about that.
"It is not me being greedy, I don't care much about money. But I want to be playing football, I want regular football.
"The club has their ambitions and plans and I hope I fit into them. I have a lot to think about but we will see what is said during pre-season and the season when it starts. There is plenty of time."