Blues boss Jose Mourinho was hoping to tie up a deal for the centre-half during the January transfer window, but the Ligue 1 outfit's valuation may deter him, The Mirror reports.
Zouma has previously been linked with Manchester United, and several other clubs from around Europe are believed to have expressed interest in signing him.
"Some clubs have launched a bid for the player, but we will not change our strategy," said Saint-Etienne co-president Roland Romeyer.
"There have been discussions for Zouma with English, Italian and French clubs, but he will not be leaving this month unless we find an agreement with some of the potential buyers.
"If not, he will have to wait until the summer. We are under no obligation to sell."
Zoumam, who is rated as one of the best young defenders in French football, is believed to have his heart set on a move to the English Premier League.