The 26-year-old only joined the Spireites in the summer on a free transfer after leaving Maidstone United.
He caught the eye playing for Dagenham and Redbridge on loan in the second-half of last season.
The Gambian-born man is Town’s joint second top goalscorer this season with five goals.
Boss James Rowe told the DT: “There has been a bid for Saidou but that has been rejected and also the player does not want to go anywhere, he is very happy where he is. I am pleased about that because you want players who are fully on-board.”
Khan has only started 11 of 22 league games this season and just one of the last five in the National League, although he did start against Chelsea in the FA Cup.
Explaining the reasoning, Rowe said: "In regards to Saidou, he needs to start hitting form again. He knows he can show more than what he is showing at the moment. Perhaps his minutes have been a little bit limited in terms of we have played quite a few away games in the last few weeks and we have set-up differently.
"He is a very talented lad and he is here for a reason. I monitored him for over a year when I brought him in. I really like his character, he is really enjoying the Chesterfield community and being part of it up here because he is a London lad.
"It is pleasing that he does not want to move anywhere because when any offer comes in for any player I always speak to them because you only want players who want to be here and he does.
"We are looking forward with him and hopefully with the minutes under his belt he can start hitting the form that he did at the start of the season.”
When asked which club made the offer, Rowe replied: "It is irrelevant, really. It is the fact a bid has come in, he does not want to go anywhere, that is forgotten and we move forward.”