The FBI is investigating the awarding of the 2018 and 2022 World Cups to Russia and Qatar as part of its wide-ranging crackdown on Fifa corruption, according to Reuters.

The American bureau, which along with the Swiss authorities arrested numerous Fifa officials in Zurich last week on corruption charges, is reportedly examining the controversial awarding of the 2018 and 2022 tournaments, whose destinations were decided in 2010. The Swiss authorities had already declared they were investigating the 2018 and 2022 bids.

Jérôme Valcke, the Fifa general secretary, has also said “I don’t feel guilty” despite being at the centre of a storm that alleges South Africa paid $10m to secure three votes for the 2010 World Cup.

“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.”

According to Reuters, an FBI official who spoke on condition of anonymity said Fifa’s decision to award the World Cups to Russia and Qatar respectively are part of an inquiry that is looking beyond the allegations in an indictment published last week that alleged endemic corruption at the world governing body.

Earlier on Wednesday, Russian officials had said Blatter’s resignation would have no impact on their preparations to host the 2018 World Cup.

“It’s not about Russia or Qatar, it’s about respect to football players,” the deputy prime minister Arkady Dvorkovich told the Guardian. “Any political interference into football affairs is illegal. Our preparations are going very well, much better than in some other World Cup countries. We have learned from them.”

Fikile Mbalula, the South African sports minister, has denied his country bribed Fifa officials in order to secure votes for the 2010 World Cup, even though a $10m payment was made to the Caribbean Football Union.

A letter from the South African Football Association in 2008 was addressed specifically to Valcke and contained detailed information about how the payment – claimed to be for a “Diaspora Legacy Programme” – should be processed.