Sepp Blatter was not present at a FIFA Medical Conference he was due to attend on Thursday amid the scandal that has rocked the governing body.
The FIFA president had been due to speak at the event in Zurich, but a spokesman revealed that the 79-year-old had pulled out due to "obvious reasons".
The governing body is in turmoil after 14 people - including nine FIFA officials - were indicted on charges of racketeering, conspiracy and corruption by Switzerland's Federal Office of Justice, following a request by United States authorities.
They were later named as FIFA vice-presidents Jeffrey Webb and Eugenio Figueredo, along with executive committee member Eduardo Li, development officer Julio Rocha, attache to the CONCACAF president Costas Takkas, CONMEBOL executive committee member Rafael Esquivel and FIFA organising committee member Jose Maria Marin.
Blatter is due to stand against Prince Ali bin Al Hussein on Friday, but UEFA called for the presidential elections to be postponed.
