It is one they would like to fill with Verstappen, who has been irrepressible for Red Bull in recent seasons, winning each of the last three world titles.
However, Verstappen has continued his dominance in 2024 with his imperious Red Bull team, making a move to a team currently scrapping for the top four in the constructors' championship very unlikely.
Mercedes pair Hamilton and George Russell could only finish sixth and ninth respectively at the Chinese Grand Prix, and Horner was scathing of Wolff's pursuit of his star man after the race.
"Why would you want to leave this team?," he asked rhetorically. "Mercedes are third team behind their customers [McLaren and Aston Martin]. His time would be better spent perhaps focusing on the team rather than the driver market.
"I can assure you that there is no ambiguity about where Max Verstappen will be next year."
Verstappen is under contract with Red Bull until 2028, and reaffirmed his commitment to their cause in Shanghai.
"I signed a long-term deal with the team. The only thing I said from the beginning is we want to have a peaceful environment," he said.
"Lately we have been talking about the car. I am happy about that. I am happy with the team and there has never been a reason to leave."