03:26

My colleague David Conn has put together this primer on what happens now after Blatter said he would step aside.

And here’s one of the key questions:

Where does this leave the planned World Cups of 2018 and 2022 in Russia and Qatar?

Greg Dyke, the English FA chairman, said immediately that Blatter’s resignation means the votes for the hosts of these two World Cups will be looked at more closely now and Qatar will be feeling uncomfortable. The stance of both countries has always been that they did not do or pay anything illicit to any of the then-Fifa executive committee members who voted, several of whom have now been proven guilty or stand accused of corruption.



On the same day as seven Fifa officials were arrested in Zurich last week, the Swiss attorney general announced a new investigation into the award of the 2018 and 2022 World Cups to Russia and Qatar. Data and documents stored in computers at Fifa were seized, as well as “relevant bank documents at various financial institutes in Switzerland”.

All 10 executive committee members who voted on the 2018 and 2022 World Cups who were in Zurich last week are to be questioned, the attorney general said, “as persons providing information”, not as suspects.



The attorney general’s statement was explicit that “irregularities” and “unjust enrichment” are suspected in the allocation of the tournaments to Russia and Qatar, and suspicions that money was laundered through Swiss bank accounts.



Sepp Blatter (right) gives the World Cup trophy to Sheikh Hamad bin Khalifa Al-Thani, Emir of Qatar, after Qatar was announced as host of the 2022 World Cup in December 2010. Photograph: Walter Bieri/EPA

Fifa sought to spin this extraordinary announcement last week as evidence of its own reforms proceeding, because in November it filed some criminal charges following its own internal investigation by the former US prosecutor Michael Garcia. The Swiss attorney general stated: “Therefore, the Swiss proceeding is aimed at persons unknown, with Fifa as the injured party.”



However the irregularities highlighted from the Garcia report by the Fifa ethics committee “adjudicatory chamber” chairman, the German judge Hans-Joachim Eckert, were relatively minor, and Eckert found they did not damage the integrity of the 2018 and 2022 World Cup bidding processes. The Swiss investigation, although it followed Fifa’s criminal complaint, appears more far-reaching, although given the questioning of all executive committee members, seems to be in its early stages.



Russia and Qatar will have huge legal claims against Fifa if the tournaments are removed from them and the votes re-run, without solid evidence that their bids, not Fifa’s own executives, were corrupt. That prospect remains a long way off, and the expensive preparations to host the tournaments in both countries are proceeding.