Christian Horner has said that time is running out for Red Bull and Toro Rosso to seal an engine deal that will keep them in F1 next year.
The Red Bull Racing team principal said that the engine situation was now critical, adding that proposals to bring the start of the 2016 season forward by two weeks only intensifies the pressure on the team as it seeks to secure an acceptable deal with Ferrari.
"The situation is quite critical because, as we sit here, we don’t have an engine," he said on Sunday after the Japanese Grand Prix.
"Toro Rosso are in a similar situation and their timing is more critical," he added. "The teams are linked and I think Dietrich’s position is pretty clear.
"We’re already late, very late. For Toro Rosso, it is more critical than Red Bull Racing. It already was difficult two weeks ago."
Having already parted company with existing engine providers Renault after a disappointing couple of seasons since they won their last championship together, Red Bull has already ruled out taking a customer deal with main rivals Mercedes and are now relying on linking up with Ferrari next year.
However Red Bull owner Dietrich Mateschitz insists he'll only do a deal if Ferrari gives them the same specification engine that it provides the Scuderia, and reports suggest that Maranello management are only willing to provide 2015-spec power units.
"The important thing for us is to have a first-class engine," explained Horner.
"First of all, we need to conclude our situation with our current supplier, but I think Dietrich has made the situation very clear in terms of what we need from Ferrari.
"We know that there is an engine available at, say, a Sauber-spec service potentially, but even that has not been promised."
And if an acceptable engine proves not to be forthcoming from Maranello, then Horner insists that he will have no choice but to look at future options for the team outside of Formula One.
"[If] we are in a position where we can’t compete then, for sure, we would have to look at other activities. Milton Keynes is full of talent and we would have to look at where we apply that talent."
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