Cyril Abiteboul has all but confirmed reports Renault and Red Bull will split after next season.
It was rumoured in the Singapore paddock recently that the French supplier has already told the energy drink-owned team that it cannot use Renault power beyond 2018.
Renault boss Abiteboul told the French magazine Auto Hebdo: "Sooner or later, Renault will have to part with Red Bull.
"But the only thing I can confirm today is that we have a contract with them for 2018."