Neither was able to take part in the GP2 winter tests as they worked to put budgets together for 2013.
"I know I am not in perfect condition since I could not complete all the pre-season tests, but I kept on working hard in case this would happen and it happened," said Berthon, who took 12th in last year's standings with Racing Engineering and claimed two podiums in sprint races.
"I feel more than ready and I am confident for this season because I have one year experience in GP2 under my belt, but also because I feel Trident is supporting me fully and they show me that they want to work and progress with me."
Ceccon contested several GP2 rounds in late 2011 in parallel with claiming the Auto GP title, before spending last year in GP3, where he was ninth in the championship for Ocean.
Trident last took a GP2 victory in Hungary in August 2011. Formula Renault 3.5 champion and Sauber Formula 1 reserve Robin Frijns was among the drivers it evaluated over the winter.
- Sports & Recreation