Christian Horner says Red Bull is expecting to know Renault's plans for the future by the Singapore Grand Prix.
Renault has been in negotiations regarding a takeover of Lotus for a number of months, but no deal has been announced. If Renault becomes a full constructor once again, it would mark the end of Red Bull's partnership with the French manufacturer, with a switch to Ferrari power units now the most likely result.
Speaking after the Italian Grand Prix, Horner said the gap between races needs to see Renault's future clarified.
“I mean obviously time is starting to press on now, we’re now into September and everybody needs to know," Horner said. "What are Renault’s plans for the future? I would have thought within the next two weeks we should all know what Renault’s position is.”
Renault has also been working on a power unit upgrade for this season, but Horner says there are no guarantees Red Bull will take the new engines.
“It hasn’t been confirmed to us when it will be or how much performance it will be either. When we understand what the performance gain is then you’ve got to weigh it up with, ‘Is it worth taking a penalty for?’ So we’ll wait to hear from Renault on that.”
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