The 23-year-old is out of contract and has been linked with several clubs following the Canaries' relegation to League One.
"I had a discussion with Lee last week about his contract situation and he's decided to keep his options open and discuss his future with other teams," Gunn told the club's official
"Obviously we wish Lee all the best, he's been a fantastic player during his time here and winning the Barry Butler Player of the Year trophy shows the fans applauded his contributions last season as well.
"Lee, within his contractual rights, exercised his options and now we wish him all the best for the future.
"I'll be sad to see him go but he sees his future higher than League One."