Sepp Blatter has written to the world’s 209 national football associations vowing not to be silenced despite his suspension as president of Fifa.

Blatter, who claims to be “bewildered” by allegations of corruption, also compares the action taken against him to the Spanish Inquisition, and says he will present his case for reinstatement with a “strong belief in justice”.

The traditional end-of-year letter, which was sent out on Monday, also calls for calm to be restored to the world governing body, after a year in which it has been rocked by the arrests of some of the game’s leading officials.

Ethics prosecutors want a life ban if corruption is proved in Blatter authorising a $2 million payment in 2011 for Michel Platini, whose ethics hearing is on Friday. Bans of several years for conflicts of interest are thought more likely.

“Although I have been suspended, I am not isolated and will certainly not be silenced,” Blatter writes.

The embattled president, who will be replaced at an extraordinary Fifa congress on February 26, also called public comments surrounding the Fifa investigation prejudicial and “dangerous”.

“The way in which the investigatory chamber of the Ethics Committee has communicated on the current proceedings, demanded the maximum penalty and reinforced public prejudgement has reached a tendentious and dangerous dimension. These proceedings remind me of the Inquisition.”

Blatter reinforces his stance that his agreement with Platini was legal, saying a verbal agreement must be adhered to, and again claims that the payment was approved by the Fifa Congress.

“I am bewildered by the insinuations and allegations brought against me,” Blatter writes. “I have always performed my duties to the best of my knowledge and belief and at all times faced up to the challenges with respect, honesty and fair play.”

As well as his own troubles, for which Blatter thanks those who have stood by him, he praises the smooth day-to-day running of the world governing body and expresses his hopes that 2016 “will be a better year.”

United States prosecutors have charged 41 people and entities in an inquiry into football corruption.

Officials from throughout the Americas are among the defendants in a case that prosecutors say involves $200 million in bribes and kickbacks tied to the marketing of major tournaments and matches.

Blatter is also the subject of a criminal investigation in his native Switzerland over the Platini payment.

The avalanche of corruption allegations prompted Blatter to say in June he would resign, only days after being re-elected to a fifth term. Blatter has not been charged with a crime.