SEPANG, Malaysia (Reuters) - Former champions Red Bull say they have no plans to make their own engine and could be forced out of Formula One if current partners Renault walk away.
"We have no intention of being an engine manufacturer," team principal Christian Horner said at the Malaysian Grand Prix, reiterating a stance that has been questioned of late as tensions with Renault come to the fore.
Horner said that if Renault decided to quit the sport, a possibility raised by Renault F1 managing director Cyril Abiteboul, then Red Bull might not be able to find an alternative.
He said that was what the team's motorsport consultant Helmut Marko had meant when he suggested after this month's Australian season-opener that Red Bull could leave.
"Should we find ourselves in a situation where we could ultimately find ourselves without an engine supplier... you could find yourself actually forced out of the sport," said Horner.
He said Mercedes were sure to refuse to supply Red Bull and the team were unlikely to be in a position to take a Ferrari engine. Honda have an exclusive agreement with McLaren.
Horner emphasized, however, that Red Bull -- who have committed to Formula One until 2020 -- wanted to continue.
"Is Formula One delivering for Red Bull as a brand? There are some worrying signs when we see races like we saw in Melbourne but hopefully that's one chapter in a long story," he added.
"Red Bull want to compete, Red Bull want to be in Formula One and we want to try and address some of the issues that are currently plaguing the sport that we don't seem to be able to find any traction with."
Red Bull's partnership with Renault, who powered them to four successive constructors' titles between 2010 and 2013, has been under strain since last year when it became clear the engine was no match for Mercedes.
The team have become more hands on with the engine side and there has been speculation they could seek to follow Mercedes and Ferrari in building both the engine and chassis despite previous denials.
"We have an amount of resource that we try to supplement and assist Renault where we can," said Horner.
"We have a strong simulation group. We have strong facilities and CFD (computational fluid dynamics) capacity within Red Bull Technology. Basically, what we're trying to do is work in co-ordination with Renault."