Christian Horner believes winning every race in the 2023 season is 'unimaginable' for Red Bull.
The reigning champions have already claimed victory at all five events so far in 2023 with Max Verstappen taking three of those.
The pace advantage the RB19 has right now is likely to close in Horner's eyes as teams continue to bring new upgrades throughout the European leg of the season.
But the Red Bull team principal refused to answer whether he thought Mercedes were being truthful about their upcoming upgrades.
Max Verstappen held onto the championship lead with victory in Miami
Tall order
"I think that's a massively tall order," Horner said in an interview with The Financial Times.
"You've got 23 events, you've got street circuits, weather that's going to turn up, probably at Silverstone.
"There's reliability, strategy, an element of luck so I think to win 23 races is unimaginable.
"If you believe Mercedes, they have a completely new car coming." The interviewer then interrupted to ask if Horner believed Mercedes to which he replied: "I'm not going to answer that question."