Dayot Upamecano has been told to sign a new RB Leipzig contract or be sold this year.
The centre-back has developed into one of the most sought-after defenders in Europe since joining Leipzig from Salzburg in 2017.
The 21-year-old has impressed consistently at the heart of the defence, although his form has tailed off since the Bundesliga season restarted and he was sent off in the 1-1 draw with Paderborn last Saturday.
Upamecano, whose contract runs until June 2021, is said to have a release clause of €60million that will expire at the end of this month.
Leipzig sporting director Oliver Mintzlaff has made it clear the club cannot consider allowing the player to leave on a free transfer in 2021.
"Upa is an extremely important player for us and one of the most sought-after talents in this position in Europe," Mintzlaff told Bild.
"One thing we can guarantee: we have a very clear understanding with him and his agent that we won't be letting him go for free. We cannot afford that as a club.
"So, there are two options: extend or change. I'm absolutely certain we'll know relatively quickly which direction we're going in."
According to Bild, Arsenal had a €60m bid for Upamecano turned down before the start of the season.
Manchester United have also been linked with the player, who began his career with Valenciennes and spent a season with Liefering in Austria before his move to Salzburg.