The bosses of Formula 1 rivals Mercedes and Renault have confirmed they are willing to co-operate on non-competitive matters, amid mounting speculation that Mercedes could yet supply engines to the Red Bull F1 team.

Mercedes and Renault-Nissan have been engaged in a joint venture partnership in road cars for almost six years, co-developing vehicles, opening factories and sharing resources together.

However, Renault, which currently has a contract to supply Red Bull with engines in Formula 1 until the end of 2016, is looking to either buy its own team or exit the sport at the end of this season. This follows constant criticism from Red Bull regarding the performance of its engines.

"We either move out or we move on - and that is the subject of ongoing discussions," said Ghosn, who added that if his firm stayed in F1, it would only supply customer engines again once it had established its own standalone team.

The decision to run its own team or leave the sport is said to hinge on whether Renault is awarded extra prize money that is afforded to teams that have historically supported F1.

Ghosn has already made it clear that whichever decision is made, the firm will not supply any customer teams with engines once current contracts expire.

To that end, speculation at the Frankfurt motor show has suggested that Mercedes could step in to either supply Red Bull with year-old engines or that an arrangement could be reached under the firms’ joint-venture partnership for Mercedes units to be rebranded by Red Bull sponsor and Renault-Nissan brand Infiniti.

Mercedes and Renault cannot co-operate on the development of technical parts because this is against F1 rules. However, Mercedes could agree to end its existing engine supply deal with the Lotus team to pave the way for Renault to buy the privateer team and rebrand it as a works concern.

Asked if the road car partners were open to co-operating in F1, Ghosn said: “I have open discussions with Dieter [Zetsche - Daimler boss] about Formula 1. We will continue to be competitive but if there are some areas that don't change the nature of the co-operation, then why not?”

Asked if he could envisage circumstances where a Mercedes engine could power a Red Bull next year, Zetsche said: "We would very much like Renault to stay in F1, but that must be their decision. If we can help with that in any way we will."

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