The Uruguay striker wrote in Spanish that "in no way [did it happen] how you have described, as a bite or intent to bite."
The player's defence is in paragraph six of FIFA's ruling, which has been seen by The Associated Press.
Suarez wrote: "After the impact... I lost my balance, making my body unstable and falling on top of my opponent. At that moment I hit my face against the player, leaving a small bruise on my cheek and a strong pain in my teeth."
But the seven-man panel ruled that the bite was "deliberate, intentional and without provocation."
The FIFA statement added: "He bit the player with the intention of wounding him or at least of destabilising him.
"In such context the committee observes that the player had been sanctioned on previous occasions in club competition for similar acts."
It also said the striker showed no remorse for his actions, adding in paragraph 29: "The disciplinary commission observed that the player at no moment showed regret or remorse of any type nor did he admit a violation of any FIFA rule and therefore in general he did not show any consciousness of having committed any offence."
Suarez was banned for nine international matches and from all football for four months -- a punishment the Uruguayan FA has said it will appeal against.
The striker has returned to Uruguay after having his World Cup accreditation revoked and being banned from the team hotel by FIFA and was given a warm reception by football fans.
Hola a todos, escribo este mensaje para dar las gracias a todas las muestras de apoyo y cariño que estoy (cont) http://t.co/2uo0LXaqs2
- Luis Suarez (@luis16suarez) June 28, 2014He, in turn, thanked his supporters via his official Twitter account, saying: "Hello everyone. I'm writing this message to give my thanks for all the displays of support and kindness that I am receiving. Both me and my family are grateful for them.
"Thanks a lot for being at my side and I want us all today to support my teammates from the national side for the game against Colombia."
Information from the Press Association was used in this report.
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