Reports in Germany claim that 22-year-old forward Schurrle has already agreed his part of a deal which could be worth in excess of £20million.
Voller travelled to England with general manager Michael Reschke to meet with Chelsea and talk terms over the highly-rated forward.
Asked about a deal with Chelsea, Voller told Bild: "Yes, I was in London and I have had discussions. There is nothing more to say, there is nothing decided yet. "
It is also claimed in the German media that Voller asked Chelsea about the possibility of taking Belgian winger Kevin De Bruyne as part of the deal.
The 21-year-old is currently impressing for Werder Bremen on loan and Bayer are hopeful that they can take De Bruyne on loan for next season.