Jose Mourinho has insisted that Andre Schurrle will only be allowed to leave Chelsea this month if the club were to receive a "phenomenal offer" for the German's services.
It has been widely speculated that the 24-year-old is eager to move on before the deadline passes in order to gain regular starting opportunities elsewhere.
However, Mourinho has claimed that only a combination of a big bid and Schurrle expressing his desire to depart would see the attacker head for pastures new.
"The principle is that we would like him to stay. The question is not to be allowed or not allowed," the Chelsea boss told reporters.
"The question is to have a phenomenal offer and a player to be super keen of accept a new challenge in his career. We don't want to sell our players."
Schurrle joined Chelsea from Bundesliga outfit Bayer Leverkusen in 2013.