A Fifa official who blew the whistle on alleged corruption within the game's governing body is to step down as general secretary of Concacaf.
Chuck Blazer will continue as a Fifa executive committee member but will leave his North and Central American and Caribbean post on 31 December.
The 66-year-old American said: "It is time for me to explore new challenges."
His allegations led to senior Fifa colleague Mohamed Bin Hammam being banned from football for life.
Another senior executive, Trinidad & Tobago's Jack Warner, resigned in June after being suspended pending an investigation into bribery allegations.
Vice president Warner and fellow Fifa member Mohamed Bin Hammam were said to have paid bribes of £600,000 to Caribbean associations.
But in a statement at the time of Warner's resignation, Fifa said: "As a consequence, all ethics committee procedures against him have been closed and the presumption of innocence is maintained."
Blazer alleged that violations of Fifa's code of ethics had occurred during a meeting organised by Bin Hammam and Warner in May.
In a statement, Warner said: "I am convinced, and I am advised by counsel, that since my actions did not extend beyond facilitating the meeting that gave Mr Bin Hammam an opportunity to pursue his aborted bid for the Fifa presidency, I would be fully exonerated by any objective arbiter.
"I have, nonetheless, arrived at the decision to withdraw from Fifa affairs in order to spare Fifa, Concacaf and, in particular, CFU and its membership, from further acrimony and divisiveness arising from this and related issues."
Warner also told Bloomberg press agency he felt he had been "hung out to dry" and insisted the giving of gifts has been part of Fifa culture during his 30 years in the organisation.
"It's not unusual for such things to happen and gifts have been around throughout the history of Fifa," he said. "What's happening now for me is hypocrisy."
He added: "I have lost my enthusiasm to continue. The general secretary that I had employed, who worked with me for 21 years, with the assistance of elements of Fifa has sought to undermine me in ways that are unimaginable.
"This is giving the impression that Fifa is sanitising itself. I've been hung out to dry continually and I'm not prepared to take that."
In May, Fifa opened "ethics proceedings" against Warner and Bin Hammam but Warner insisted he was not guilty of a "single iota of wrongdoing".
Football's governing body then suspended Warner and Bin Hammam on 29 May, pending an investigation into claims they had offered bribes to members of the Caribbean Football Union (CFU).
Despite claims by Bin Hammam that Fifa president Sepp Blatter was aware of payments made to the CFU, and that he too should be investigated, Fifa's ethics committee stated that "no investigation is warranted" of Blatter.
Following Bin Hammam's suspension, Blatter went on to run unopposed in the Fifa presidential election, despite efforts by the FA to have the election suspended amid the corruption allegations that had engulfed the sport's world governing body.
Blatter was re-elected for a fourth term after receiving 186 of the 203 votes, after 16 other member associations supported the FA's request for a delay.