Bayer Leverkusen chief Simon Rolfes insists Jonathan Tah won't leave in January.
Chelsea are keen on the Germany international, who's contract carries a buyout clause of €18m.
A move in January has been mooted - and Tah is also wanted by Bayern Munich.
The defender has just changed agents. Tah is now represented by Pini Zahavi, which may indicate that a move is in the offing.
But Rolfes insists: "We won't be giving away any players in the winter."