FIFA President Gianni Infantino is the subject of criminal proceedings launched by the Swiss Federal Public Prosecutor, Stefan Keller.
The proceedings come after complaints made over meetings between Infantino, Michael Lauber, the Swiss Attorney General, and the chief public prosecutor of the Swiss region, Upper Valais, Rinaldo Arnold.
The investigation follows Lauber's resignation last week, after a court upheld allegations that he had lied about meeting Infantino. The Attorney General had been in charge of an investigation into the 2015 corruption scandal which resulted in indictments against senior figures at FIFA.
In a statement, FIFA said it acknowledges the decision to open a new investigation and says it will cooperate fully.
"People remember well where FIFA was as an institution back in 2015, and how substantial judicial intervention was actually required to help restore the credibility of the organisation," said Infantino, making a statement through FIFA.
"As President of FIFA, it has been my aim from day one, and it remains my aim, to assist the authorities with investigating past wrongdoings at FIFA. FIFA officials have met with prosecutors in other jurisdictions across the world for exactly these purposes. People have been convicted and sentenced, thanks to FIFA’s cooperation, and especially in the United States of America, where our cooperation has resulted in over 40 criminal convictions.
“Therefore, I remain fully supportive of the judicial process, and FIFA remains willing to fully cooperate with the Swiss authorities for these purposes."
Infantino denies any wrongdoing, and highlighted a comment he made in June: "To meet with the Attorney General of Switzerland is perfectly legitimate and it’s perfectly legal. It’s no violation of anything. On the contrary, it is also part of the fiduciary duties of the President of FIFA."
The Swiss Office of the Attorney General said that Keller had found indications of criminal conduct, and said in a statement: “This concerns abuse of public office, breach of official secrecy, assisting offenders and incitement to these acts.
“Additional criminal acts and the commencement of further proceedings remain reserved.”