The FIA is insisting that McLaren and Lewis Hamilton 'misled' the governing body during a meeting with stewards following the Australian Grand Prix.
Hamilton was stripped of his third place in Melbourne on Thursday, while Toyota's Jarno Trulli was reinstated to third place, after the FIA stated that the Italian was 'unfairly penalised' for overtaking the McLaren behind the safety car.
Both Hamilton and Trulli were summoned by the stewards after the incident last Sunday. Trulli was penalised 25s, which dropped him out of the points.
On Thursday, McLaren team boss Martin Whitmarsh denied the team had lied to the stewards.
However, the FIA said on Thursday afternoon that both Hamilton and team manager David Ryan had not been completely honest about what happened during the race.
"During the hearing, held approximately one hour after the end of the race, the Stewards and the Race Director questioned Lewis Hamilton and his Team Manager David Ryan specifically about whether there had been an instruction given to Hamilton to allow Trulli to overtake," the FIA said in a statement.
"Both the driver and the team manager stated that no such instruction had been given.
"The race director specifically asked Hamilton whether he had consciously allowed Trulli to overtake. Hamilton insisted that he had not done so."
The FIA added that both in radio communications and in an interview after the race, it was clear that McLaren had instructed Hamilton to let Trulli through.