Max Verstappen has called on Honda to keep on bringing more powerful engines to the grand prix circuits.
But Verstappen observed that Renault, Red Bull's former supplier, is now taking obvious steps forwards.
"Even McLaren was very fast on the straights," the Dutchman said.
"I am pleased with the balance of the car, but we need to keep working on it in order to remain competitive. And we need a more powerful engine."
Earlier at Paul Ricard, Verstappen had said the Renault-powered cars were suddenly faster particularly in qualifying thanks to a 'party mode' setting.
"We definitely have something that will appear in the next races," said Verstappen when asked if Honda must follow suit.
"We can see that Renault get a noticeable power increase with a special operating mode of the engine."
F1 is now heading to Red Bull's home race in Austria, where thousands of Dutch fans are expected to flock.
"It will not give me an increase in engine power," Verstappen smiled. "I am always glad to see the fans but I am not expecting miracles."body check tags ::