Max Verstappen has cast doubt on Renault's ability to be competitive in 2019.
The Dutchman has been vocally critical of Red Bull's departing engine supplier at recent races.
Renault boss Cyril Abiteboul has announced that, due to limitations with the existing design, the French manufacturer will use an almost completely new power unit in 2019.
"I'd have to see it," Verstappen, to be Honda powered next year, said in Austin.
"Four years ago they said that too, then three years ago, then two years ago. It's always the same song.
"But it doesn't matter to me, I'm not looking at that at all. I'm looking forward to the challenge with Honda," he added.
Verstappen said he also has doubts about the 2019 chassis regulations that are designed to improve overtaking.
"It might help a little bit, but what I'm already reading is that next year we'll have about the same downforce as this year, so I think that the benefit will be limited," he told verstappen.nl.
"It only looks somewhat uglier, but maybe the design will be refined before the next season."
Finally, Verstappen brushed off news that Austin has added a new kerb at the corner that he controversially cut en route to the US grand prix podium a year ago.
"There are still so many other corners you can cut," he told reporters in Austin. "That I did it there last year was a coincidence. It just happened that way."
