The Danish striker, who has been loaned out to Sunderland and Juventus over the past two seasons, thought that his Gunners career was over when he returned from the Old Lady in the summer.
There was reported interest in him from Premier League clubs, such as Crystal Palace, but Arsenal eventually decided on keeping him after failing to sign any notable competition for Olivier Giroud.
However, Bendtner has insisted that he still wants to leave the Emirates Stadium and has claimed that he is training as seriously as ever in a bid to find form for his potential new employers.
"I was very disappointed when he (Arsene Wenger) phoned because I was ready to move on. I didn't actually think that they wished to keep me," he told reporters. "As I have been at the club since I was 16 I found it ridiculous that they placed me in the reserves and let me train on my own.
"[But] suddenly everything was like old times again. I was training with the first team, I was hanging out with the first team and I had a dietician again. From being completely out to being completely in again.
"I am training far more seriously [now] than I have ever done in Arsenal. I am in the process of building myself up so that I become this strong machine, this perfect product to sell. I want to start as strongly as possibly in my next club."
Bendtner is currently second choice to Giroud at Arsenal and has made six appearances for them in all competitions this season, although just one has come from the start.