Russia and Qatar's hosting rights for the 2018 and 2022 World Cup tournaments were thrown into doubt last night after Sepp Blatter, the head of football's governing body, was finally forced to relinquish his iron grip on the sport.
Mr Blatter made the unexpected announcement that he would quit as president of Fifa in a hastily arranged press conference at the association's Zurich headquarters last night.
It prompted speculation that his decision was the result of a new development in an international police investigation into alleged bribery and corruption in the organisation.
Greg Dyke, the chairman of the English Football Association, said: "Clearly there's a smoking gun. It's not to do with Sepp Blatter being honourable."
Sources last night said that Mr Blatter was being investigated by the FBI and US prosecutors as part of the same investigation that led to the arrests last week of seven current and former Fifa officials.
Mr Blatter had been re-elected as president of Fifa for another four-year term only on Friday, having resisted calls from some of the sport's most respected voices to quit.
He said he had made the decision to stand down because of a "lack of support in the world of football". He added that he would leave as soon as a replacement could be elected, which Fifa said may be as late as next March.
Mr Blatter fell on his sword hours after the emergence of a letter that suggested Fifa had lied over the identity of an official who had handled a $10m (€9m) payment, said to have been a bribe.
The letter was viewed as evidence of the extent to which investigators from the Swiss authorities and the FBI - who are now working together - have been able to access internal Fifa documents, and perhaps even computer servers at the organisation's headquarters.
It has been reported that several US officials told 'The New York Times' that they are hoping to gain the co-operation of some of the Fifa figures now under indictment on charges of racketeering and money laundering to try to build a case against Mr Blatter.
The Fifa president had refused to consider any rerun of the bid process for the Russia 2018 and Qatar 2022 World Cups in light of corruption allegations, but his absence could open the way for a thorough review of the controversial decisions.
Mr Dyke said: "If I was in Qatar today I wouldn't be feeling very confident. I think [the news] is long overdue, but it is good news for world football. It now means that we can get in there and find out where all the money has gone over all these years and sort it out for the future."
England, one of the countries that bid unsuccessfully for the 2018 World Cup, will now be alert to the possibility that it could yet win the right to stage the tournament if Fifa's 2010 voting process is declared null and void by Mr Blatter's eventual successor. England would be in a position to host a World Cup at short notice, having the stadiums and the infrastructure in place.
While Russia may take comfort from the argument that it is now too close to the 2018 tournament to change the host nation, Qatar, which has been mired in controversy over the deaths and working conditions of migrant labourers building its stadiums, will be seen to be far more vulnerable.
Mr Blatter had suppressed the publication of a report into the 2018 and 2022 vote by Michael Garcia, a former US attorney, a decision that led to Mr Garcia's resignation.
Any new candidate for the Fifa presidency would have to run on a manifesto promising transparency, making the publication of the potentially damning report far more likely.
Mr Blatter had woken up to the news that 'The New York Times' had uncovered evidence that his deputy, Jerome Valcke, was the man behind a $10m bank transfer from Fifa accounts to accounts controlled by Jack Warner, a former Fifa vice-president now accused of taking a bribe in exchange for helping South Africa to win the right to host the 2010 World Cup.
Fifa issued a strong denial of Mr Valcke's involvement, saying the person involved was Julio Grondona, an Argentinian official who died last year. Just an hour later a leaked letter to Mr Valcke from the South African FA was published online which appeared to show that Fifa had lied. (© Daily Telegraph, London)