Zurich: FIFA president Sepp Blatter's payment to Michel Platini, chief of Eurpean football governing body UEFA, was a "conflict of interest", according to Domenico Scala, chairman of the world football governing body's audit and compliance committee.
Blatter, 79, and Frenchman Platini, 60, are suspended while FIFA investigates reports that a 1.35 million pound payment was made in 2011 for work Platini did as Blatter's adviser.
Platini claims the deal was an "oral contract" for work done from 1998-2002. Both men deny any wrongdoing, Financial Times reported on Tuesday.
Scala said the payment was not recorded in the accounts in 2002 and called that a "serious omission".
Blatter is stepping down as president after 17 years, with FIFA confirming on Tuesday that it would elect his successor on February 26, 2016.
Platini maintains he still wants to stand for the next presidency, but FIFA said it cannot recognise his candidacy while his ban is in place and he cannot campaign.
"In any normal business, there would be a written contract," Scala said.
"Both parties were members of FIFA's executive committee and knowingly approved each year financial statements which were incorrect by 2 million Swiss francs (1.35m pound). That could be seen as falsification of the accounts,” he said.
The payment was made in February 2011. Platini later ruled out standing against Blatter in that year's FIFA election, saying he wanted to concentrate on running UEFA.
Both men are appealing against their "provisional" 90-day suspensions -- put in place while FIFA's ethics committee completes an investigation into two of the game's most powerful figures.