Dr Helmut Marko has denied that Max Verstappen vetoed Red Bull's top driver choice for 2019.
Red Bull is considering which driver should replace the Renault-bound Daniel Ricciardo next year.
At the top of the shortlist are Carlos Sainz and Pierre Gasly, but reports have suggested Dutchman Verstappen vetoed Sainz after their time together at Toro Rosso.
Red Bull official Marko told Diario Sport: "The rumours are wrong. Red Bull is the one who decides about drivers."
For his part, Sainz is not jumping the gun.
"At the moment I'm still a Renault driver," he told Auto Motor und Sport.
"If Red Bull asks me to come back, that would of course change. I owe Red Bull a lot. The mutual respect is great.
"I also have a very good relationship with Helmut Marko. It's thanks to him that I'm in F1."
The 2018 calendar continues with the Belgian Grand Prix on August 26.
