A former senior UN official has pleaded guilty to accepting hundreds of thousands of dollars in bribes.
Alexander Yakovlev is the first UN official to face criminal charges over the oil-for-food program.
The US attorney's office said he had pleaded guilty to conspiracy, wire fraud and money laundering and had been released on bail.
The money was paid to Mr Yakovlev, who worked in procurement, by foreign companies trying to win UN contracts.
His actions were uncovered by the inquiry into the oil-for-food program, although only one charge related to that operation.
Mr Yakovlev resigned from the UN earlier this year.
The investigators into the oil-for-food program also found that the former director, Benon Sevan, was given money by an oil company in return for helping them to win lucrative contracts, reports BBC News.
According to Newsday, the Independent Inquiry Committee led by former U.S. Federal Reserve chairman Paul Volcker reported Monday that it had also uncovered enough evidence to prosecute two of Sevan's friends who are related to former U.N. Secretary-General Boutros Boutros-Ghali. They are suspected of helping the ex-director in a kickback scheme.
The committee, which is a fact-finding body and cannot file criminal charges, accused Sevan of steering lucrative Iraqi oil contracts to a company run by the two Egyptians and accepting $147,184 in kickbacks. For the first time, it gave a motive, saying his finances were "precarious" before the kickbacks started.
Sevan dismissed Volcker's charges as "false." He lambasted U.N. Secretary-General Kofi Annan and the U.N. Security Council, which set up the oil-for-food program. And he accused the inquiry committee of a "witch-hunt."
At the urging of Volcker's investigators, Annan waived Yakovlev's immunity on Monday after David Kelley, the U.S. attorney for the Southern District of New York, requested that he do so.
The investigators also asked Annan to assist in the possible prosecution of Fred Nadler, a brother-in-law of Boutros-Ghali who is a director of African Middle East Petroleum Co. Ltd. Inc., and Fakhry Abdelnour, the Swiss company's president and a cousin of the former secretary-general.
The inquiry committee found Yakovlev secretly tried to bribe a company called Societe Generale de Surveillance S.A., which was seeking an oil inspection contract under oil-for-food. But they also came across more explosive evidence of wrongdoing _ that Yakovlev took at least $950,000 in kickbacks from companies that had won some $79 million in U.N. contracts unrelated to oil-for-food.