Sepp Blatter is "bewildered" by allegations he faces and will go before the FIFA ethics committee on Thursday with "a strong belief in justice".
"Although I have been suspended I am not isolated and will certainly not be silenced," Blatter wrote to 209 FIFA member federations.
Ethics prosecutors want a life ban if corruption is proved in Blatter authorising USD 2 million in 2011 for Michel Platini, whose ethics hearing is on Friday.
Bans of several years for conflicts of interest are thought more likely.
Blatter said public comments from the FIFA investigation are prejudicial and "dangerous".
He pledged to "continue to fight for my rights," and appeal to the Court of Arbitration for Sport.
Blatter sent his traditional end-of-year letter on personal headed notepaper instead of FIFA's.