Christian Horner has indicated that the Andretti-Cadillac/General Motors bid needs to build its own Formula 1 engine as it seeks F1's approval to join the grid.
The FIA announced on October 2nd that Andretti had been accepted under its Expression of Interest process, and the bid would be moved onto Phase 3 of the process which is commercial discussions with the Commercial Rights Holder (CRH).
However, F1 and the teams are reluctant to welcome Andretti onto the grid as the prize pot would need to be split 11 ways instead of 10 with some squads worried about their positions being weakened by Andretti's arrival.
Audi is set to enter in 2026 like Andretti have planned, but is doing so having bought Sauber with Ford also coming in as technical partner to Red Bull, whose Team Principal Christian Horner believes Andretti-GM must build its own engine.
This is something GM has not ruled out, but it is understood to be something for the future and not immediate upon a successful entry to the grid.
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Horner's Andretti advice
"I see this very much as an issue between the FIA and Liberty Media," Horner told Sky Sports F1.
"The FIA is the regulator, Liberty are the promoter and therefore they control the funding of the sport and of course, with another team coming in, how is that going to be funded?
"Those guys need to get together and come to us with a proposal of what they want.
"To have General Motors coming in to Formula 1 is a massively positive thing, and we're seeing Ford come back in 2026, so Ford vs GM would be fantastic.
"But ideally, I think they need to do their own engine.
"When you look at how Audi is coming into the sport, they've acquired an existing team (Sauber), and an existing franchise.
"Should it be different for others? I think that's where Liberty and the FIA need to get together and come to us with a collective position because you can't have one rule for one and another for others."