Fifa will lack credibility as long as Sepp Blatter remains president, according to Michel Platini.
Blatter is seeking to extend his 17-year tenure by winning a fifth term in office in the upcoming presidential elections.
Fifa has faced intense scrutiny in recent times, particularly over claims of corruption relating to the bidding process for the next two World Cups, while the organisation has been urged to do more to improve human rights conditions in 2022 host nation Qatar.
Uefa president Platini insists that he has no personal issue with Blatter but nonetheless believes that the Swiss should stand down for Fifa's sake and the good of the game.
"I have nothing against Sepp. I like him as a person and I respect him. We have had some good times together, and nothing and no one can take that away," he said in an interview with L'Equipe.
"[But] he does not have to lie. We all know that it [standing for re-election] is not because he has not finished his mission or because he still has big plans for Fifa.
"After 40 years at the head of an institution, that speech cannot be credible. No, he is simply afraid of tomorrow because he has dedicated his life to Fifa, so much so that he identifies with it completely.
"I understand the fear of that emptiness that he must have, it's natural. But if he really loves Fifa, he should have put its interests ahead of his own.
"And while he remains in place, whether he likes it or not, Fifa will lack credibility and its image will be tarnished."
Michael van Praag and Luis Figo both withdrew from the presidential race last week, leaving Prince Ali Bin Al Hussein as Blatter's only remaining rival.
Platini is thus desperately hoping that the 39-year-old Jordanian remains in the running and ultimately emerges triumphant.
"I maintain, personally, [my support for] Prince Ali," he added. "I am convinced that Prince Ali, who I know personally, will make a great president of Fifa.
"He has all the qualities. He has been president of a national federation for 15 years, he was a member of the executive committee of his federation and vice-president of Fifa."