Manama - Gianni Infantino slammed "fake news" surrounding FIFA in an impassioned speech to the annual congress of world football's governing body in Bahrain on Thursday.
Infantino - elected as president last year on the back of FIFA's greatest scandal but who has been criticised for his commitment to real reform - also claimed corruption could "never again" happen.
"Sadly the truth is not necessarily the truth, but it is what people believe is true," he told a packed hall of delegates.
"Fake news, alternative facts, these terms did not until some time ago, they have become en vogue."
He continued: "There's a lot of fake news and alternative facts about FIFA circulating, FIFA-bashing has become a national sport, especially in some countries."
But, alternating between English, French, German and Spanish, Infantino said his organisation was now different.
"FIFA has changed now, this is a new FIFA and we are new people here and we act with facts, not with words.
"Nunca mas - never again," Infantino added in reference to corruption once more rearing its ugly head.
He also told those who wanted to enrich themselves through football to leave FIFA.
"If there is anyone in this room or outside of this room who still thinks he can enrich himself, he can abuse football, I have one clear and strong message to tell him: leave, leave football and leave football now," added Infantino.
His speech came after criticism earlier in the week after the FIFA Council recommended that the ethics judge who helped bring down Sepp Blatter, Hans-Joachim Eckert, and chief investigator Cornel Borbely not be re-elected by Congress.
Infantino also criticised "highly-paid experts" who did little to help reform.
"In the past, many highly-paid experts paid millions have been hired by FIFA to help reform FIFA, but what did they do? They simply rubber-stamped a wrong system."
In a wide-ranging speech, the Swiss president also added that FIFA was now a democracy and not a dictatorship.
He said the sport had to boost women's football and raised the prospect of a "world women's league", which he said was under consideration, but gave no further details
Infantino also advocated examining the issue of transfer regulations.
Earlier this week it was revealed that FIFA would investigate the world-record £89.3m transfer of Paul Pogba to Manchester United from Juventus in August 2016.