The panel that conducted the investigation criticized Annan's management of the $64 billion U.N. humanitarian aid program, a committee report released Wednesday showed.
Former U.S. Federal Reserve chairman Paul Volcker, who headed the Independent Inquiry Committee, said the blame for the program's failure was shared by the Security Council, other members of the United Nations and Annan's senior advisers.
Volcker suggested the U.S. Security Council and Annan change the way they do business or face a worldwide loss of public support.
Investigators said the oil-for-food project was so poorly managed that former Iraqi leader Saddam Hussein raked in $1.7 billion in kickbacks from participating companies and $11 billion in oil-smuggling profits, the report said.
But the panel found no conclusive evidence Kofi Annan knew of his son's activities. The secretary-general later said he accepted the report's "criticism," but dismissed calls for his resignation.