Mercedes has denied Helmut Marko’s claim the German marque "didn’t want" to supply Red Bull with engines in 2010.
Dr Marko, the motor sport advisor to Dietrich Mateschitz, said this week that Mercedes rejected Red Bull’s approaches because "they knew that if we had that engine, they wouldn’t see us (on the track)".
But a Mercedes spokesman told the Cologne newspaper Express: "McLaren was (our) exclusive partner and did not agree.
"Mercedes would have leased its engine to Red Bull, and these facts are well known to Red Bull," the spokesman added.
The spokesman also rejected Austrian former GP driver Marko’s claim that Mercedes has eked out an unfair engine advantage despite the freeze on performance development.
"Everything that our engineers do is strictly in conformity with the regulations and with the knowledge of the FIA. The FIA would gladly confirm this," he added.