Bayer Leverkusen director Rudi Voller has warned Chelsea that Kai Havertz will not be sold on the cheap and will remain at the club for at least another couple of weeks.
The Blues are believed to have made signing the Germany international their primary target, having already added Hakim Ziyech and Timo Werner to their attacking ranks.
Leverkusen value Havertz at £81.5m and Voller will not consider cashing in for anything less, even during a period of financial uncertainty for clubs.
The 60-year-old has also informed Chelsea that the in-demand attacker will see out the rest of Bayer's Europa League campaign, which resumes on Thursday with a last-16 second leg against Rangers.
"It is set in stone. There is no new stance," he told German outlet Kicker when asked if Leverkusen will consider selling Havertz early.
"There will also be no 'corona bonus'. No matter who the player is."
Chelsea's domestic campaign concludes on Saturday when they take on London rivals Arsenal in the FA Cup final at Wembley.