Spa-Francorchamps: Mercedes will not open any discussions with Red Bull about a possible Formula One engine supply until Renault`s future in the sport is clear, the German carmaker`s motorsport director Toto Wolff said on Saturday.
With speculation swirling at the Belgian Grand Prix that Red Bull are seeking an early exit from their partnership with Renault, if their current engine partners do not decide to quit anyway, Wolff remained guarded.
"We said, and this is still the situation, that we will not interfere into an existing relationship for many reasons," the Austrian told reporters.
"Legally, we don’t do this and it’s not the way we approach business in general and then you must not forget that Renault and Daimler go back a long way...we have a very amicable industrial relationship.
"That is why we said that until that is resolved between the two parties (Renault and Red Bull) we will not even start any discussion...it hasn’t reached that point and the complexity is quite large with many decisions to be made."
Former champions Red Bull have a contract with Renault, who also supply sister team Toro Rosso with engines, until the end of next season.
However, Renault, whose engine has been eclipsed by Mercedes since the introduction of the V6 turbo hybrid power unit last season, are weighing up whether to buy their own team or withdraw from the sport.
Both Renault and Red Bull have said publicly that they intend to honour their contracts and do not comment on speculation.
Paddock speculation has linked Red Bull to Mercedes, however, as the most likely option in the event of Renault deciding to leave.
The German manufacturer already supplies four of the 10 teams -- their own title-winning works outfit, Williams, Force India and Lotus, who switched from Renault at the end of last year.
However, financially-troubled Lotus`s future remains clouded in uncertainty with speculation they could be bought back by previous owners Renault.
Ferrari, who have previously supplied Red Bull and Toro Rosso, have indicated they would be willing to do so again in the event of Renault pulling out while Mercedes have appeared reluctant but may now be softening their stance.