Former US federal prosecutor Michael Garcia has resigned as chief corruption investigator for FIFA on Wednesday after football's governing body rejected his appeal against the handling of his report into the votes for the 2018 and 2022 World Cups.
Garcia attacked the "lack of leadership" by FIFA over the inquiry into the 2010 votes that awarded the 2018 World Cup to Russia and the 2022 tournament to Qatar.
FIFA president Sepp Blatter said he was "surprised" at Garcia's decision, but other influential figures, including UEFA president Michel Platini, said the resignation was a "new failure" by FIFA.
Garcia said he had found "serious and wide-ranging issues" in the bid process for the 2018 and 2022 World Cups.
"The lack of leadership on these issues within FIFA leads me to conclude that my role in this process is at an end," Garcia said in a statement.
Garcia quit as head of FIFA's investigatory chamber one day after the governing body rejected his appeal over the followup to his 18 month inquiry.
The resignation is now set to dominate a FIFA executive meeting in Marrakech, Morocco, on Thursday and Friday.
"I am surprised by Mr Garcia's decision. The work of the Ethics Committee will nonetheless continue," Blatter said in a statement.
Garcia had complained that a summary of his report released by FIFA's top judge Hans-Joachim Eckert was "incomplete and erroneous."
Eckert had insisted there was no evidence of corruption and that there should be no new vote for the 2018 or 2022 World Cup hosts.
The departure of the top US lawyer increases pressure on the FIFA leadership ahead of the executive committee meeting.
Blatter said however that the Garcia inquiry "will be a central part of the discussions" in Morocco.
Some reports have said executive members will press for a vote on whether Garcia's report should be released in full.
Garcia's statement said the climate at FIFA has changed for the worse in recent months.
He said that for two years after being named head of the FIFA investigatory chamber in July 2012, "I felt that the Ethics Committee was making real progress in advancing ethics enforcement at FIFA. In recent months, that changed."
Garcia reaffirmed that his report had "identified serious and wide-ranging issues with the bidding and selection process."- 'Transparency' crisis –
The lawyer complained about the "insufficient transparency" shown by FIFA and Eckert's "selection and omission of material from the report" he prepared. Eckert released a 42 page summary of Garcia's 350 page report in November.
Garcia said that his presentation to the FIFA appeal committee had said that "no principled approach could justify the Eckert decision's edits, omissions, and additions."
FIFA's appeal committee said Garcia's appeal was "not admissible" because Eckert's summary was not a formal "decision" on the case and there was nothing to appeal.
Garcia could go to the Court of Arbitration for Sport (CAS) but he said this "would not be practicable."
"No independent governance committee, investigator, or arbitration panel can change the culture of an organization. And while the November 13, 2014, Eckert decision made me lose confidence in the independence of the Adjudicatory Chamber, it is the lack of leadership on these issues within FIFA that leads me to conclude that my role in this process is at an end," Garcia declared.
The FIFA executive has faced a storm of calls, including from Platini, to release more details of Garcia's report.
"FIFA's ethics committee was created to increase transparency at the organisation, that's what we wanted, but in the end it has just caused more confusion. Mr. Garcia's resignation is a new failure for FIFA," Platini said.
Blatter, who will stand for re-election next year and is almost certain to win a fifth term, and Eckert have said the report cannot be released for legal reasons.
Platini has called on Blatter to stand down when his current term ends.
Jerome Champagne, a former FIFA official who has said he will stand against Blatter for the FIFA presidency, called Garcia's resignation "a step backwards" for the governing body.
"We needed to know what happened before and after the December 2, 2010 vote. Today more than ever we need to know," Champagne said in a statement.