FIFA has announced that it has released secretary general Jerome Valcke on leave from his duties until further notice after being made aware of allegations over a deal for 2014 World Cup ticket sales.
Reports earlier on Thursday had implicated Sepp Blatter's right-hand man in a scheme to sell World Cup tickets above face value and share the profits.
Valcke, who has been in his position since 2007, denied the allegations but has nevertheless been suspended by the organisation in light of the claims.
A FIFA statement said: "FIFA has been made aware of a series of allegations involving the Secretary General and has requested a formal investigation by the FIFA Ethics Committee."
FIFA has been the subject of much controversy since May, when Swiss police raided a hotel in Zurich and arrested seven of its top executives over claims of corruption.
Valcke said in July that he intended to leave his position when a new president is appointed next year, after he was accused of authorising a bribe to award the 2010 World Cup to South Africa.