Cyril Abiteboul has denied that Renault's upgrade for its home race in France next weekend amounts to a 'B spec' car.
"Please keep the ball flat," he told Auto Motor und Sport. "It's part two of our recovery plan."
The German report said Renault's Paul Ricard upgrade includes a new front wing, nose, bargeboards, floor, cooling system and tighter rear end.
It could be worth as much as half a second per lap, in line with Renault's pre-season aim of getting closer to the top three teams Mercedes, Ferrari and Red Bull.
But Abiteboul warned: "I hear that Haas is bringing something new as well. They'll be fast on a circuit like Paul Ricard."
After a difficult start to 2019, however, Renault is pleased to now be moving forwards, especially as the latest engine upgrade was also a success.
"The best news is that we don't have to worry about power circuits anymore," said Abiteboul.
He was speaking after Renault finished sixth and seventh in Canada.
"My grin was almost as wide as Daniel's (Ricciardo)," he smiled. "We finally delivered what we had planned before the season."