BID FOR PRESIDENCY
Blatter has called the payment, which was made nine years after Platini finished working for FIFA as an adviser, a "gentlemen's agreement".
Both men have denied wrongdoing but the affair has thrown grave doubt over Platini's bid to replace Blatter as FIFA president in an election scheduled for February 26.
Suspended FIFA secretary general Jerome Valcke's "ongoing proceedings" were also confirmed. The ethics committee said his case "related to the suspicion of misuse of expenses and other infringements of FIFA's rules and regulations".
Valcke was suspended by FIFA in September shortly after he had been accused by a ticket-dealer of having been part of a scheme to sell World Cup tickets at a marked-up price.
The committee also said six other former FIFA executive committee members were under investigation. All have been suspended or have resigned from office.
"Formal investigation proceedings relating to the suspicion of infringements of the FIFA Code of Ethics are amongst others ongoing against Worawi Makudi, Jeffrey Webb, Ricardo Teixeira, Amos Adamu, Eugenio Figueredo and Nicolás Leoz," said the statement.
Cayman Islander Webb, president of the Confederation for North and Central America and the Caribbean, was arrested in May as one of 14 officials and sports marketing executives indicted on corruption charges by the US Department of Justice.
Seven of those named by the ethics committee on Wednesday were members of the FIFA executive committee which voted in December 2010 to hand the World Cup hosting rights for 2018 to Russia and 2022 to Qatar.
Three members of that committee, former Caribbean official Jack Warner, American Chuck Blazer and Mohammed Bin Hammam of Qatar, have been banned for life. South Korean Chung Mong-joon was banned from the game for six years by the ethics committee earlier this month.
That means 11 of the 22 men who voted to back Russia and Qatar have been banned or are under investigation.