Mercedes boss Toto Wolff says he's surprised by Red Bull's strong response to his recent comments on the team's Honda power unit.
The Japanese manufacturer supplied new power units to Red Bull and AlphaTauri last week in France and the change coincided with a boost in straight-line speed of the former's RB16B.
After Max Verstappen's win on Sunday, Lewis Hamilton suggested that Red Bull had used a new and improved engine, a comment echoed by Wolff who said that Mercedes' rival had made "a huge step forward with their power unit".
Red Bull team boss Christian Horner said he was baffled by the suggestions, reminding Mercedes that all engines were homologated once and for all at the start of the season and that upgrades are not allowed.
Wolff clarified his comment, while Red Bull pointed to the RB16B's rear wing as the source of the car's strong straight-line speed.
After snatching pole on Saturday at the Red Bull Ring, Verstappen was asked about the performance of Honda's engine at higher altitudes.
The Dutchman responded tongue-in-cheek by saying that he would supply a "print out" to the media to prove that the bulls straight-line speed gains are due to the RB16B's rear wing set-up rather than its power unit.
But Wolff wondered why Red Bull felt the need to repeatedly protest his benign comments from last week and keep the topic on the table.
"I wonder why that is such a topic, when we all know that the power units need to be homologated," Wolff said.
"I’m really surprised that the Red Bull guys keep protesting so loudly on the power unit story. So that is a bit weird.
"The rules are very clear. It’s homologated, you can come up with reliability fixes, and that’s it.
"Obviously there are certain things you can clean up, but you have your tokens and you need to use them, and that’s it.
"So there shouldn’t be any power advantage as such."
Wolff followed up by saying that a strong engine wasn't the only factor behind Red Bull's current superiority over Mercedes.
"It’s always the interaction between a strong power unit, lots of downforce and making the tyres work," he said. "And I think they are just doing a very good job.
"We’ve already seen it in Ricard where they were able to run a smaller wing whilst not losing a lot through the twisty bit. So overall just a very strong package."
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