A war of words between Renault's Cyril Abiteboul and Max Verstappen escalated on Friday in Sochi when the Red Bull driver accused the Frenchman of "moaning" about him all the time.
The pair's bicker started when Abiteboul responded to Verstappen claim that Red Bull had reverted to Renault's B-Spec engine in Russia as a provisional measure because the manufacturer's latest C-Spec unit would not perform at its full potential at Mexico's upcoming high-altitude venue.
Abiteboul dismissed the driver's claim, insisting the change had nothing to do with altitude issues, suggesting Verstappen should "focus on his car".
Verstappen sent back a dig of his own to the Renault Sport F1 boss.
"If he would concentrate a little bit more on his own team instead of moaning about me all the time, they would already be world champions," Max told Ziggo Sport.
"I don't understand these things. He just has to concentrate on himself. I always concentrate on myself when I'm in the car.
"I don't think that's the issue, but we'll see."
Addressing his remarks on Renault's C-Spec engine, Verstappen insisted he was referring to the altitude issue as a potential reliability problem, not as a performance constraint.
"That man is just frustrated," said Verstappen. "I'm just very honest. I just explained clearly why we have to revert back to the B [spec].
"That turbo won't last in Mexico and Brazil. If we would race with that [engine] then we would not make it to the finish for sure.
"So, it's not that I'm lying. I just think that he can't take it very well, that I am too realistic and too straightforward.
"I demand a lot from the equipment, but I'm here to win. I'm not here to become seventh like they are doing."
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