Reigning GP3 Series champion Esteban Ocon has returned to Enstone to take up the role of reserve driver at Renault.
Ocon, 19, was affiliated with the outfit courtesy of his association with Gravity Sports and participated in free practice for the 2014 Abu Dhabi Grand Prix.
Ocon picked up Mercedes backing in 2015 and collected the GP3 title, his second successive championship triumph after picking up the Formula 3 crown in 2014.
Ocon was unveiled during Renault's official comeback launch at Guyancourt on Wednesday, alongside Kevin Magnussen and Jolyon Palmer.
Ocon will continue his affiliation with Mercedes this year, despite his role at Renault.
"Even in my new role as third driver for Renault, I remain a long term member of the Mercedes family, and I have to thank Mercedes and Renault for making this possible," he said.
"There are some opportunities out there to race as well this season but nothing has been decided yet.
"It is an incredible opportunity to be guided and supported by Toto [Wolff] and Mercedes – and to have the honour of representing a brand like Renault in Formula 1."