Fifa president Sepp Blatter is being investigated by US officials as part of their inquiry into corruption at the world football body, US media say.
The news came hours after Mr Blatter, 79, announced that he was stepping down from his role.
US prosecutors launched a criminal inquiry last week, with seven Fifa officials arrested in Switzerland, part of a group of 14 people indicted.
Two days after the arrests, Mr Blatter was re-elected president of Fifa.
However, he said on Tuesday that it appeared the mandate he had been given “does not seem to be supported by everyone in the world”.
Mr Blatter said: “Fifa needs profound restructuring.” He said he would continue in post until an extraordinary congress is called to elect a new president.
No dates have been set, but it is expected to take place between December 2015 and March 2016.