When the January transfer window opens on Tuesday next week, the £7.5million release clause in the 27-year-old striker's contract becomes active once again.
That has already sparked a flurry of speculation, just as it did during the summer, that he will leave the St James' Park outfit, for whom he has scored 27 goals since his arrival in June 2011.
The clause was not triggered during the close season and, having failed in their attempts to negotiate it out of his deal since, the Magpies are not prepared to deal with the uncertainty once again should he stay.
Pardew said: "Really and truly this window is the key, I think, because if Demba goes in this window, it will cause us a problem.
"I think he will stay but there's a possibility he could go because of the clause that's still in force.
"In the summer, I won't let it run until the summer. I'll do something about it.
"We will either move Demba on or we will secure him in the summer."
Pardew is understandably keen to retain Ba's services and the Senegal international, who has been linked with Saturday's Barclays Premier League opponents Arsenal, Ligue 1 club Paris St Germain, as well as QPR in recent weeks, has repeatedly spoken of his happiness on Tyneside.