Updated

A list of the foreign companies approved by Saddam Hussein (search) to do business under the United Nation's oil-for-food program doesn't just name names — it also provides insight into how the system worked.

The list, obtained exclusively by FOX News, appears to show that the United Nations (search), which was supposed to monitor every contract, either didn't know what was going on or turned a blind eye to a system of alleged bribes and kickbacks.

Here's how the system is thought to have operated: Saddam and his top officials would select contractors to supply humanitarian and other goods. The regime routinely would use this power to reward companies or nations that backed Saddam and argued against sanctions. The selected companies then won the privilege of becoming the dictator's preferred business partners.

But the companies didn't need to actually supply the goods they'd won the contract for. They could act as middlemen, take the contract to another company and sell it for a healthy profit. Russian and Saudi Arabian companies were the big winners in the scheme, according to the list of companies obtained by FOX News.

The gatekeepers of the system included Saddam, his secretary Abdel Hamoud, Vice President Taha Ramadan (search), and Saddam's sons Uday and Qusay Hussein.

Under the oil-for-food program, which began in December 1996 and officially ended in November 2003, Saddam's government could sell unlimited quantities of oil provided the money went primarily to buy humanitarian goods and toward reparations to 1991 Gulf War victims.

"What were U.N. officials, such as Benon Sevan (search), who ran the oil-for-food program, doing while this murky trading arrangement went on?" asked a congressional investigator who wished to remain anonymous.

"If they didn't know about it, then their monitors on the ground in Iraq were at the least incompetent," the investigator told FOX News. "If they did know, and did nothing about it, then it would seem they themselves were part of the corruption."

When FOX News asked a U.N. spokesman for his response Friday, he said it's not the organization's fault because "that's the way the system was set up."

A three-member panel led by former Federal Reserve Chairman Paul Volcker (search) is investigating the oil-for-food scandal. The panel does not have subpoena authority and will rely instead on voluntary cooperation from governments, U.N. staff, members of Saddam's former regime and current Iraqi leaders.

The panel has said it has evidence that dozens of people, including top U.N. officials, took kickbacks from the $67 billion oil-for-food program.

The General Accounting Office (search), the U.S. Congress' investigative arm, estimated in March that the Iraqi government pocketed $5.7 billion by smuggling oil to its neighbors and $4.4 billion by extracting kickbacks on otherwise legitimate contracts.

FOX News' Jonathan Hunt contributed to this report.