Reports suggested the European champions have all but wrapped up the signing of 18-year-old Serbia star Markovic, who has been heavily linked with a move to the Barclays Premier League.
But Partizan sporting director Ljubisa Tumbakovic told Sportski Zurnal: "I swear on my mother that I really do not know anything about this.
"On Saturday, I spoke with club president Dragan Djuric and he also told me that he knows nothing about Markovic's transfer to Chelsea.
"I don't know, he doesn't know. Maybe the journalists have better information than us in the club!"
Reports had claimed Chelsea were on the brink of finalising a deal, with the major remaining stumbling block being whether Markovic joined them in January or next summer.