The Senegalese striker has a release clause in his contract for a fee of around £7million and Pardew suggests he may make the decision to leave in January to the likes of Arsenal or Liverpool if it suits him.
"It's unfortunate that the contract he has leaves open a lot of questions because we have this clause and every window that comes around, I have to answer the same questions," Pardew told reporters.
"It would be disappointing for him to leave in this window for this club and for his teammates here, but the decision will be his, ultimately, because that clause is there.
"The most important things we have got with Demba is he is someone who is a goalscorer and he is scoring goals, and that's very, very important to a side. His commitment to and work-rate for the team, I don't fault."