FIFA has urged the Football Association and the Sunday Times newspaper to provide reports and evidence that there was impropriety in the 2018 and 2022 World Cup bidding process.
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Those at the head of world football's governing body have expressed extreme concern'' at the latest allegations of World Cup bidding corruption, after former FA and England 2018 chairman Lord Triesman claimed that four FIFA members had asked for money or favours in return for World Cup votes.
Two other FIFA members were separately alleged to have been paid $1.5 million to vote for Qatar's 2022 bid.
FIFA said in a statement: "In his letter to the FA, the FIFA secretary general [Jerome Valcke] expresses the extreme concern of FIFA and the FIFA President at the latest allegations questioning the integrity of some FIFA Executive Committee members in connection with the bidding procedure for the 2018 and 2022 FIFA World Cups.''
"He adds that to be in a position to examine the situation thoroughly and with clear-sightedness, FIFA asks the FA to submit a complete report from Lord David Triesman, by means of which the latter would relate his declarations fully and provide any and all documentary evidence at his disposal.''
The allegations of bribes paid for votes for Qatar were contained in a submission to the culture, media and sport committee by the Sunday Times.
"The FIFA secretary general has also sent a letter to the Sunday Times to ask the newspaper to provide FIFA with any piece of evidence with regard to the statements made to MP John Whittingdale," the statement continued. "The Sunday Times had already provided world's football governing body with all of the evidence and documentation at its disposal.
"Nevertheless, FIFA asks the English newspaper to submit as soon as possible any other piece of evidence that it may be in possession of and which has not yet been sent to FIFA. In particular, reference is made in the letter to the allegations regarding a 'whistleblower who had worked with the Qatar bid', who allegedly made some declarations regarding the matter in question.''
FIFA presidential candidate Mohamed Bin Hammam, a key figure in Qatar's successful 2022 World Cup bid, has strenuously denied claims the country paid bribes for votes and also called for evidence to be produced.
"I can assure you nothing like this has happened from our side," Bin Hammam said. "If someone wants to damage reputations like this then they have to provide the proof. You can't just accuse people just like that.
"It didn't happen. It is fine to say something, to try to damage the reputation of somebody but where is the proof?''
FIFA president Sepp Blatter has said he wants to resolve the matter before the governing body's presidential election. "We have to do it now immediately. We have exactly three weeks to do so," Blatter told Al-Jazeera.