FIFA presidential hopeful Mohamed Bin Hammam launched a blistering attack on rival Sepp Blatter on Thursday, accusing the Swiss official of sullying the organisation "beyond compare".
Bin Hammam, the president of the Asian Football Confederation, criticised Blatter's decision this week to allocate 20 million euros of FIFA money to an anti-corruption taskforce run with Interpol.
"It has become clear yet again in recent days that something urgently needs to be done to improve and enhance the image of FIFA," Bin Hammam wrote on his blog. "The name of our great sport and its leading institution have been dragged through the mud once more."
"I will happily and unreservedly restate that I firmly believe FIFA, as a decision-making body and as an organisation, is not corrupt."
Bin Hammam's comments came after a British parliamentary committee heard evidence on Tuesday that six members of FIFA's executive committee had requested favours ahead of the votes for the 2018 and 2022 World Cups.
Bin Hammam, who has rejected any suggestion of corruption in Qatar's successful 2022 bid, added that under Blatter's regime "it is impossible to deny that the governing body's reputation has been sullied beyond compare and it is time for that to change."
"Currently, the president has taken on too much of an executive role, as evidenced by the recently announced initiative to donate 20 million euros to Interpol. Imagine FIFA financing Interpol's activities!"
"This decision was taken arbitrarily by the FIFA president and was not discussed with the executive committee."
"It is just another example of the current regime choosing to run football how it sees fit, rather than doing so in a manner that is consistent with the governing body's proper procedures."
Bin Hammam, once a close ally of Blatter, will attempt to unseat the long-serving Swiss official at a June 1 election in Zurich.
He said a new regime was required to clean up FIFA's image.
"How on earth can we convince people of FIFA's innocence?" he wrote.
"A new atmosphere needs to descend upon FIFA; there needs to be an opportunity for new ideas to take hold and for the organisation to take a new direction."
Bin Hammam faces an uphill battle however, with the Oceania confederation following in the footsteps of UEFA on Thursday by confirming their support for Blatter at next month's vote.
Blatter meanwhile has been invited to appear befor the British parliamentary committee that aired the corruption allegations earlier this week.