F1's governing body will be "on their toes" in 2010 to scupper renewed suggestions of bias towards Michael Schumacher.
Damon Hill, the German driver's fierce championship opponent of the mid 90s, told the BBC: "The suspicion was always that Michael got a little bit of favouritism from the FIA."
Schumacher, to turn 41 on Sunday, retired from the grid at the end of 2006, and his then Ferrari boss Jean Todt is now the president of the FIA.
Todt has described his relationship with Schumacher as almost akin to father and son.
"I think the FIA are going to have to be on their toes to make sure that there is no suspicion of that (favouritism) in the coming season," 1996 world champion Hill added.
Frenchman Todt, 63, was asked about Schumacher's decision to return to F1 with Mercedes in an interview with Le Figaro newspaper.
"He is part of my family, but it would be inappropriate for me to discuss his decisions," he said. "I leave it to him to comment."