As revealed by HITC Sport last week Greek champions Olympiacos had made an enquiry for the former England under-21 international as they look to bolster their defensive options.
Olympiacos are looking to freshen up their squad before the close of the transfer window after crashing out of the Champions League in the qualifying rounds to Israeli side Hapoel Beer Sheva and had hoped to bring in versatile performer Mancienne to bolster their options.
However, Mancienne, who is entering the final year of his contract at Forest, has rejected the approach at Olympiacos as he is not interested in a move to Greece.
Mancienne, who missed Forest's opening day of the season win over Burton Albion at the weekend, has established himself as a key player at Forest since his arrival at the City Ground in 2014.
Forest manager Philippe Montanier is reluctant to lose any of his players as he looks to build a squad capable of challenging for promotion this season