"We are absolutely confident that the power units used by Mercedes, Force India and ourselves are identical in terms of both hardware and software"
Thursday 13 December 2018 16:20, UK
Williams have refuted suggestions they played a role in pressurising the FIA to issue a technical directive around F1 engine parity.
In January, F1's governing body issued a directive stating that engine suppliers must give identical power units to customer teams as the manufacturer teams run, with the same software and operating conditions.
Red Bull team principal Christian Horner suggested the media should "go and speak to Claire Williams" where the new focus on parity had come from.
But Williams have denied lobbying the FIA on the issue.
"Contrary to comments made recently in the press, we refute any suggestion that we have questioned the parity of the power units provided by Mercedes-AMG HPP," Williams said in a statement.
"We are absolutely confident that the power units used by Mercedes, Force India and ourselves are identical in terms of both hardware and software.
"We have an excellent professional and personal relationship with Mercedes, and our focus is firmly on continuing the good work that we have started, as we prepare for the final test in Barcelona this week ahead of the new season."
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The FIA's directive sent to the teams in January stated that while its dossier system "is to ensure that all power units supplied by one manufacturer are identical in all respects, we have good reason to believe that this may not be the case.
"Whilst the dossiers for each team may be identical it would appear that some are being operated in a different way to others being supplied by the same manufacturer.
"It is therefore our view that all power units supplied by one manufacturer should be identical, not only in terms of the dossier for each team being the same, but we also feel they should be operated in an identical way."
Mercedes boss Toto Wolff did not believe either of their customer teams, Williams and Force India, had lobbied the FIA and insisted both teams had always received identical power units to the world champions.
"Identical modes for the customers and us. There has never been any difference. They have the same mileage allowance as the works team, there is no difference whatsoever," he told Motorsport.com.
"That's why we have no problem with that. If there is any suspicion out there, it certainly wasn't anything that would have any consequence for us.
"We have the belief that sharing modes and engine calibration among six cars triggers a steeper learning curve for us than running different engine specifications between the customers and the works team."
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