Suarez was hit on Thursday with a nine-game suspension on playing competitive matches for Uruguay and a four-month ban from any football-related activity, a record punishment for a player at a World Cup.
The decision ended the involvement in the tournament in Brazil of one of the sport's best players and prompted fury in the South American nation at the scale of the punishment for Suarez who was given a hero's welcome on his return.
"At no time did the player show any kind of remorse or admit to any violation of FIFA rules and therefore showed no awareness of having committed any infraction," the FIFA document, seen by Reuters on Saturday, said.
The document, drawn up by FIFA's Disciplinary Committee which heard the Suarez case, said the bite on Italy defender Giorgio Chiellini on Tuesday took place when the two players were not close to the ball, which was an aggravating factor, and was a "deliberate, intentional and unprovoked" act.
The document said a six-game ban - the minimum in cases of a player spitting at another player - was considered insufficient in this "extraordinary" case.
The decision to also ban Suarez from any football-related activity for four months was taken because the committee members felt two previous bans on Suarez for biting, while playing for clubs in Europe, had been ineffective.
A FIFA spokeswoman said she could not comment on the case as discussions by the Disciplinary Committee were confidential.
Brazilian newspaper Estado de Sao Paulo reported on the document detailing the committee's decision earlier on Saturday.
It included excerpts of Suarez's explanation of the event, in which he said his initial contact with Chiellini caused him to lose balance and fall on the Italian.
"Then, my face hit the player, leaving me with a bruise and a lot of pain in my teeth which caused the referee to stop the game," Suarez was quoted as saying.
"That is what happened and at no point did anything happen that can be described as 'biting' or trying to bite," he said.
The Disciplinary Committee meeting which ruled on the Suarez case included representatives of Pakistan, the Cook Islands, Singapore, Panama, Hong Kong, South Africa and Switzerland, the newspaper reported.
Uruguay have told FIFA they intend to appeal the ban which they say is excessive, a view shared even by Chiellini.
Uruguay face Colombia in the World Cup's first knockout round on Saturday.