The Chelsea winger is currently on loan at Werder Bremen, and has the pick of three German clubs this summer – Leverkusen, Borussia Dortmund and Schalke.
Leverkusen want him to join on a season-long loan as a direct replacement for Schurrle while Dortmund are ready to splash out £15m to sign him permanently.
But Leverkusen sporting director Rudi Voller insists any deal for Schurrle cannot be completed without his club getting De Bruyne in return.
After negotiations with Chelsea earlier this week, the two clubs are thought to have largely agreed as to the intracacies of the Schurrle transfer but the deal now hinges on De Bruyne’s decision.
Voller said: “It was good to meet Chelsea officials, and the discussions went well, but no decision has been made yet.”
The report claims Leverkusen are willing to pay a £2m loan fee to secure De Bruyne next season, a figure which will reduce Chelsea’s total outlay for Schurrle to £18m.
Voller and his assistant Michael Reschke returned to Germany on Friday afternoon after talks with the Stamford Bridge hierarchy in London.