FIFA president Sepp Blatter, under criminal investigation by Swiss authorities, plans to remain in his job until February and has told staff at the world football governing body that he has done nothing illegal or improper, Blatter’s lawyers have said.

An emailed statement from Blatter’s personal lawyers, Lorenz Erni of Switzerland and Richard Cullen of the United States, also defended payments that Zurich-based FIFA made to Michel Platini, president of the UEFA football confederation, as “valid compensation” for Platini’s work as an adviser.

Swiss prosecutors said on Friday they had opened a criminal investigation into Blatter on suspicion of criminal mismanagement and misappropriation of funds.

Authorities interrogated Blatter at FIFA headquarters and seized unspecified data from his office.

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The prosecutors said Blatter was suspected of a “disloyal payment” of 2 million Swiss francs ($2.94 million) to Platini in 2011 at the expense of FIFA, said to have been for work performed between January 1999 and June 2002.

Blatter told Swiss authorities on Friday that Platini “had a valuable employment relationship with FIFA” as an adviser, Blatter’s personal lawyers said.

“He explained to the prosecutors that the payments were valid compensation and nothing more and were properly accounted for within FIFA including the withholding of social security contributions,” the lawyers said.

Platini made his own defense of the payments on Tuesday morning.

The one-time star for France said in a statement that he had not been accused of wrongdoing and that the money was fully declared to authorities in accordance with Swiss law.

Platini said he has offered to speak to FIFA’s Ethics Committee to help resolve any issues relating to the 2011 payment.

“I wish to clarify that for the period 1998 to 2002, I was employed by FIFA to work on a wide range of matters relating to football,” the Frenchman wrote.

The 60-year-old Platini did not address why the payment came nine years after he finished the work with FIFA but said he wants to clear his name swiftly.