Former FIFA Executive Committee member Chuck Blazer, meanwhile, has alleged he was bribed to vote for South Africa’s successful bid for the 2010 World Cup.

According to Reuters, the American investigation, made public last week with the indictment of 14 FIFA officials for racketeering, conspiracy and corruption, will now scrutinise both bid processes, throwing the possibility of a revote back into the limelight.

Previously, it was the Swiss authorities who targeted their inquiry at the two tournaments but reported FBI involvement could see further probing into the 2018 and 2022 competitions, both of which have been embroiled in a storm of bribery allegations.

Also today, American Blazer revealed he had admitted in a 2013 testimony to a New York City judge that he and "others on the FIFA Executive Committee agreed to accept bribes in conjunction with the selection of South Africa as the host nation for the 2010 World Cup".

This was said to have begun “in or around 2004 and continuing through 2011”. 

It follows an historic day for football yesterday where current President Sepp Blatter made the surprise announcement at a hastily-arranged press conference in Zurich that he was to step down froma role he has held since 1998.

In another twist, the American media are reporting that Blatter is being investigated as part of the United States Department of Justice (DoJ) inquiry into widespread corruption in football, where nine FIFA officials and five other executives were indicted.

The DoJ confirmed Central America and Caribbean Association Football (CONCACAF) President Jeffrey Webb of the Cayman Islands was one of those arrested in the dawn raids at a Swiss hotel in Zurich ahead of the FIFA Congress last week.

China's Eduardo Li, Nicaraguan Julio Rocha, Costas Takkas, Uruguay's Eugenio Figueredo, Venezuela's Rafael Esquivel and Brazil's José Maria Marin were the others to be detained.

The claims of the Swiss’ involvement were neither confirmed nor denied by Attorney General Loretta Lynch, who refused to comment due to the fact that the investigation is ongoing.

“It's an open case and so we will now be speaking through the courts,” Lynch said.

The Swiss authorities confirmed yesterday that Blatter, whose reign as FIFA President has been plagued with allegations of corruption and other misdemeanours, was however not part of their investigation.

Interpol has placed Warner and former Executive Committee member Nicolás Leoz on its wanted list and issued Red Notices for both men, as well as four other corporate executives, though these are not international arrest warrants.

One of the main payments at the centre of the FBI’s corruption inquiry relates to an alleged $10 million (£6 million/€9 million) donation to Warner in exchange for his support for South Africa’s eventually-successful bid to host the 2010 World Cup.

FIFA claimed neither Jérôme Valcke nor "any other member of FIFA’s senior management were involved in the initiation, approval and implementation of the...project".

Shortly afterwards, however, a letter from SAFA outlining the scheme and dated March 4, 2008, surfaced.

This was addressed to Valcke at FIFA in Switzerland.

The Secretary general, considered a close ally of Blatter, insists he can carry on his capacity despite the accusations levelled at him.

“I have no reason to say that I shouldn’t remain secretary general regarding what’s happened in the last days, because I have no responsibility,” he told France Info radio.

“I’m beyond reproach and I certainly don’t feel guilty.

“So I don’t even have to justify that I’m innocent.”

South African Sports Minister Fikile Mbalula also moved to dismiss claims the payment was a bribe, saying he "categorically denies that our country and Government bribed anyone to secure the rights for the 2010 FIFA World Cup".

"We frown upon allegations that suggest that South Africa has paid a bribe," he added.

"We also clarify that payments made for approved projects can never be construed as bribery and that any insinuation to the contrary will be met with our rebuke.

“The fact that a payment of $10m was made to an approved programme above board, does not equate to bribery."

Blatter’s surprise resignation, which sent shockwaves through the footballing world, came just four days after he was successfully re-elected for a fifth term as head of world football’s governing body after only challenger Prince Ali Bin Al Hussein opted to pull out following the first round of voting.

It has also been suggested today that the Jordanian Football Association are exploring the possibility that Prince Ali, who has already confirmed his desire to stand in the race to be Blatter’s successor, could in fact take over at the helm of world football in an interim capacity before an official replacement is elected.

Based on FIFA statutes, four months’ notice is required for any Presidential Election to be held, with FIFA chairman of Audit and Compliance Committee Domenico Scala suggesting that it will take place within the period of December 2015 to March 2016.

A host of candidates have already been touted, including current UEFA President Michel Platini, one of the only FIFA members to have revealed he voted for Qatar in the 2022 bid race.

The Frenchman opted to cancel a meeting of UEFA members, where Blatter’s re-election was on the proposed agenda, in light of recent developments.

Other names in the frame are David Ginola, who was widely lambasted for a tame attempt to enter this year’s Presidential Election race which was backed by funds provided by a bookmaker, and current Association of National Olympic Committees (ANOC) President Sheikh Ahmad Al-Fahad Al-Sabah of Kuwait, a new arrival on FIFA’s Executive Committee.

Britain’s David Gill, who had said he would refuse to take up his vice-presidency within FIFA if Blatter was given a fifth term in office, Frenchman Jerome Champagne and Luis Figo are also reportedly poised to enter the fray.

One of the latest names to be allegedly queuing up to become involved in the race is former vice-president Chung Mong-joon after the South Korean said he would “carefully think about it before making a decision on whether to participate in the FIFA presidency election”.

Former Brazilian international Zico has also announced his intention to stand.

Blatter meanwhile received a 10-minute standing ovation from 400 staff at the organisation’s headquarters, where he urged his “fantastic team” to “stay strong”.

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June 2015: David Owen: Sepp Blatter’s long goodbye
June 2015: Blatter to step down as FIFA President
June 2015: Alan Hubbard: FIFA takes sleaze to new levels even by the terrible standards of sport
June 2015: FIFA’s Independent Ethics Committee provisionally bans three officials as crisis continues
May 2015: Top South African official confirms $10 million World Cup payment was made by FIFA