A Red Bull boss has accused Toto Wolff of spreading negative rumours about the team in a recent interview.
Red Bull have been blighted by instability in 2024, with their team boss Christian Horner embroiled in controversy, in addition to the departure of their technical chief Adrian Newey.
Change will further impact the team in 2026, where they will compete with their own powertrains in partnership with Ford.
However, rumours suggest that their engine development is not going according to plan, with people internally concerned about the project that coincide with F1's regulation changes.
Wolff doubts Red Bull Powertrain project
Mercedes team principal Toto Wolff has also expressed his doubts regarding Red Bull’s engine project, after Christian Horner raised concern over the 50/50 power split that will be introduced in 2026.
"I think what frightens him [Horner] more maybe is that his engine programme is not coming along, and maybe he wants to kill it that way. You always have to question what is the real motivation to say something like that," Wolff said according to Autosport.
However, Red Bull boss Helmut Marko has refuted claims that the team are concerned over their 2026 engine, with the 81-year old hitting back at Wolff.
"Guess who is spreading these rumours?" Marko said to oe24, referring to Wolff. "We are right on schedule."
Whilst Marko seemed assured the project is fine, he also revealed that there is no Plan B for their project if it does not start working right away.
"Our engine has to work or start working immediately," Marko added.
"There are so many factors involved, such as the fuel and the battery. It will be exciting to see who will really be at the front. Regarding the horsepower, we will definitely be there."