"I am supporting him no longer, it's finished," said Platini. "He knows it, I told him. I think FIFA needs a new breath of fresh air."
Platini, who himself had to come out last week and deny he had been pressured by former French President Nicolas Sarkozy to vote for Qatar in the controversial and scandal-tainted bid race for the 2022 World Cup, said he agreed with his fellow UEFA members that it was time for 78-year-old Blatter, who has been in power since 1998, to call it a day when his mandate ends next year.
"I share the European position," said 58-year-old Platini. "A new mandate for him would not be good for football. But he is a person one has to respect and he has all my respect."
Blatter, who has been under pressure over the controversy-plagued 2022 Qatar World Cup, had declared to the FIFA Congress in Sao Paulo on Wednesday that he was ready for a new mandate despite having said in 2011 he would not seek re-election for a fifth term.
"I'm ready to accompany you in the future," he said to the assembled FIFA members, though, his announcement was greeted by some boos.
Platini, who won great praise in 1998 for his organisation of the World Cup hosted by France, indicated that he and his members had not been happy with the Congress.
Several of Platini's colleagues had openly confronted Blatter on Tuesday when he addressed their association telling him that his claims the British media's motivation in investigating the Qatar bid were "racist" were without foundation.
The FIFA leader was helped by a congress vote not to consider age- and term-limits for officials. He later denied having any designs on a life-time presidency
"Well it wasn't the Europeans who blocked the reforms, it was clear who voted against the age limit," said Platini.
However, Platini still would not commit himself to a run for the FIFA presidency.
At present there is just one candidate -- former FIFA deputy secretary-general Jerome Champagne.
"It is an option to run but it is not because Sepp Blatter is a candidate that Michel Platini won't be," said Platini.
"In any case this situation it is not exactly as if I have to choose in between going to hospital or to prison," he said laughing.
Blatter has long been a controversial figure, and FIFA, which oversees a multi-billion dollar industry, has never been far from scandal.
Just prior to the World Cup, Britain's Sunday Times published a series of reports alleging that millions of dollars in bribes were paid to help Qatar secure the 2022 edition.
Blatter succeeded scandal-plagued Brazilian Joao Havelange in 1998. Under his stewardship, football's revenues have mushroomed, with huge amounts from television rights and sponsorship.
But it has also attracted scandal, the latest of which is led by media reports that Qatar's Mohamed bin Hammam paid more than five million dollars in bribes to win support for World Cup.
Qatar has denied any wrongdoing, but the scandal has still tainted the build-up to the start of the World Cup on Thursday.