Lewis Hamilton demanded change at the very top of Formula One after lambasting the FIA's investigation into his boss Toto Wolff and wife Susie as "unacceptable and disappointing".
Hamilton was speaking at the federation's prize-giving gala in Baku an hour after Wolff revealed Mercedes are considering taking legal action against the FIA following its compliance inquiry into claims of an alleged conflict of interest with Susie, who is the managing director of the F1 Academy.
A day after the FIA announced its controversial investigation into the Wolffs, the sport's nine other teams said they had not complained and, on Thursday night, the FIA said there was "no ongoing investigation" before closing the case.
On another day of twists, the FIA's president Mohammed Ben Sulayem had been due to face the media, but he was pulled from his press conference after the federation said he was hospitalised with concussion following a fall several days ago.
The FIA said Ben Sulayem, 62, who is set to appear at the prize-giving ceremony on Friday night, will make a "full recovery".
"It has been a challenging week, and a disappointing week to see that the governing body has sought to question the integrity of one of the most incredible female leaders we have ever had in our sport in Susie Wolff without questioning and without any evidence," said Hamilton.
"And then just saying 'sorry' at the end. That is unacceptable.
"We have a lot of great people in the sport doing amazing work and there is a constant fight to improve diversity and inclusion within the industry.
"But it seems there are certain individuals in the leadership of our sport that every time we try to make a step forward they try to pull us back and that has to change.
"This is a global sport and we have such an incredible opportunity and natural responsibility to be leaders of change. We need to make some changes to make sure we are all pushing in the right direction."
Forty-eight hours after the FIA said its compliance department was "looking into" the allegations which arose in Business F1 magazine, the federation said on Thursday that it "can confirm that there is no ongoing investigation in terms of ethical or disciplinary inquiries involving any individual".
But team principal Wolff, who has overseen six of Hamilton's record-equalling seven world championships, said Mercedes are in an "legal exchange with the FIA".
"We understand that there is significant media interest in the events of this week," said the Austrian, 51, in a statement.
"We are currently in active legal exchange with the FIA. We await full transparency about what took place and why, and have expressly reserved all legal rights. Therefore we ask you for your understanding that we will not be commenting officially for now, but we will certainly address the matter in due course."
Susie Wolff, who in her role as boss of the all-female F1 Academy reports to F1 CEO Stefano Domenicali, had already vehemently denied the allegations - calling them "intimidatory and misogynistic".
However, on Friday she took another swipe at the FIA shortly before her husband's statement was released.
"When I saw the statement issued by the FIA yesterday evening, my first reaction was: 'Is that it?'," she said on social media.
"For two days, insinuations have been made about my integrity in public and through background briefings, but nobody from the FIA has spoken to me directly.
"I might have been collateral damage in an unsuccessful attack on somebody else, or the target of a failed attempt to discredit me personally, but I have worked too hard to have my reputation called into question by an unfounded press release.
"We have come a long way as a sport. I was extremely thankful for the unified support of the Formula 1 teams. I have worked with so many passionate women and men at F1 and the FIA, who have the very best interests of our sport at heart.
"However, this episode has so far taken place without transparency or accountability. I have received online abuse about my work and my family. I will not allow myself to be intimidated and intend to follow up until I have found out who has instigated this campaign and misled the media.
"What happened this week is simply not good enough. As a sport, we must demand, and we deserve, better."
