Haas Formula 1 team principal Gunther Steiner has been fined €7500 for causing "moral injury" to a steward and harming the reputation of motorsport and the FIA.
Immediately after Kevin Magnussen had finished ninth in the Russian Grand Prix, Steiner took to team radio to support his driver and criticise a five-second time penalty that cost him a position.
Steiner's message, which was not played out to this extent at the time, included: "If we didn't have a stupid idiotic steward we would be eighth.
"You know who is the steward. You know him. It is always the same.
"He just does not get any more intelligent."
As revealed by Autosport following the race, Steiner's comments were poorly received by FIA officials and the authority to deal with the issue was delegated to the Japanese GP stewards.
Steiner was therefore summoned to see the Japanese GP panel, comprising Le Mans 24 Hours legend Tom Kristensen, Gerd Ennser, Dennis Dean and Yasuhiro Yodono, on Friday at Suzuka.
The issue could not be dealt with on the day it had occurred because "certain members" of the Haas team had already left the circuit in Russia and there was also "a potential conflict" with one of the stewards.
According to their report, Steiner confirmed his comment was targeted at one specific member of the Russian GP panel and had no objection to the Japanese GP stewards dealing with the case, despite the chairman of the stewards - Ennser - being the same for both events.
After the hearing, the stewards announced they had opted to fine Steiner €7500 for the incident.
They reported that Steiner said he "regretted his choice of words", which were "spoken in the heat of the moment after a hotly contested race by his drivers".
They added: "He did not intend for his words to reflect unfavourably on the FIA officials of the event and the championship."
But the stewards pointed out it was "an insult to the stewards of the event and calls into question both the skills and the integrity of those stewards".
They have determined that Steiner "caused moral injury to FIA officials" and "was prejudicial to the interests of motorsport" with his comments.
"Such statements harm the reputation of motorsport in general, the FIA in particular, and call into question the professionalism of the officials of the FIA," the report continued.
"While any factual criticism of steward panel decisions is always welcomed in private discussions with that panel, public personal attacks against individual officials are totally inappropriate and will not be accepted."
Explaining the punishment, the stewards said it was considered appropriate given no prior penalties have been imposed on Steiner for similar behaviour.
"However, in the event of future violations, it may become necessary to consider whether a team should be penalised, along with any individual involved, with harsher sanctions," the stewards warned.