The head of the inquiry, former U.S. Federal Reserve Chairman Paul Volcker, said Hussein diverted some $1.8 billion in kickbacks and surcharges.
The firms involved include internationally known companies. The report says some of those firms took part knowingly, others inadvertently.
The report finds Russian, French and Chinese firms were given favorable treatment by Iraq. Russia, French and China are all permanent members of the UN Security Council.
Russian politicians and companies were heavily implicated in the report.
It cites Iraqi documents showing the Russian Communist and Liberal Democratic parties companies each receiving large oil shipments for their support of Iraq.
Volcker said the report showed a pattern of favoritism by the Iraqi regime.
"Saddam plainly chose to favor those nations, companies, and individuals that he felt, rightly or wrongly, would assist his efforts to end the sanctions imposed at the end of the Gulf War," Volcker said. "It's also true, as our early reports have emphasized, that political differences and pressures within the United Nations organization itself -- the Security Council, the secretariat, and some UN agencies -- frustrated appropriate and effective response to the manipulation and corruption of the program."
The report says Russian companies contracted for about $19.3 billion worth of oil from Iraq, about 30 percent of all oil sales during the time of the program.
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