Borussia Dortmund insist Neven Subotic is not for sale after Manchester City were linked with a £20million bid for the defender.
Speculation on Sunday claimed City boss Mark Hughes had lined up the 20-year-old as the next big-money arrival at the club in January.
Hughes brought in Kolo Toure and Joleon Lescott during the summer, but reports claim he wants further additions to his backline.
Subotic is highly rated in Germany and the former Mainz youngster has previously been linked with City's Premier League rivals Arsenal, Chelsea and Everton.
However, Dortmund general manager Hans-Joachim Watzke is adamant Subotic will not be leaving the club in New Year even if City make a £20m offer.
"They could easily make us this offer if they would like to," said Watzke.
"But we are staying firm to our vow - Neven Subotic is not for sale."
Subotic, who signed a new five-year contract in the summer, is flattered by City's reported interest, but is in no rush to leave the Bundesliga club.
He told BILD: "It is a big honour if such a big club is attempting to sign me, but I am under contract until June 2014 at Borussia Dortmund and still want to achieve many things with this club."
