Werder Bremen sporting executive Frank Baumann has said the club will not sell Serge Gnabry during the winter transfer window.
Gnabry, 21, joined Bremen from Arsenal in the summer for a fee reported to be in the region of €5m.
"We will certainly not give him away after only a few months," Baumann told Kreiszeitung. "And he does not want to leave either, I am dead certain."
He said Bremen would not allow Gnabry to move even if a club were to make a huge offer, adding: "We need Serge in the New Year."
Gnabry has been linked with Bayern Munich, who are reported to have the first option on him, but earlier told Bild: "There's nothing to say about this."
On Friday, he won his first senior cap for Germany against San Marino, scoring three times in an 8-0 win.
That made him the first player to score a hat trick in his first appearance for Germany since Dieter Muller against Yugoslavia in 1976.
Gnabry feared he was the victim of a practical joke when national team coach Joachim Low gave him a call last week to say he was part of his squad.
"The coach called me and I had to consider for a while whether it was real or not," he told RND radio. "There have been a lot of these fake calls on the radio and I just didn't want to be the next victim."
The Werder Bremen midfielder finally convinced himself that he really was speaking to Low and he paid him back for his faith with a hat-trick in San Marino, penning the next chapter in a successful season on a personal level.
With four goals, he is Bremen's top scorer in the Bundesliga following his summer switch from Arsenal, to whom he owes a huge debt of gratitude.
"Without being in England, I would not be the player I am now," he said. "There was Arsenal's quick playing style, for example, which I learned.
"When you are a young player and you get to train with such top players as there are at Arsenal for three years then of course you take something away with you and it improves you.
"That was definitely the case with me. I probably would not be here now if I had not been in England."