The French carmaker returned to full works status in F1 last year.
But as former team champion Fernando Alonso goes on the driver market for 2018, Renault has delivered the message that it will not be ready to give the Spaniard a title-winning car.
Current driver Nico Hulkenberg, however, told Le Point: “We are progressing. We are on track.”
Team boss Cyril Abiteboul agrees: “Next year, Renault will be able to settle in just behind the top teams Mercedes, Ferrari and Red Bull.”
The report said “the majority of the staff” at Enstone and Viry are already working on the 2018 car, with Abiteboul promising an “extremely innovative” car-engine package.