John Bolton (search) made clear Wednesday that he believes the United Nations (search) has systematic management problems, but the new U.S. ambassador to the world body said he held out hope that those problems could be fixed.

If they are, Bolton said, the United Nations should be allowed in the future to run operations like the much-criticized Oil-for-Food program (search).

"There may be an occasion that we want the U.N. to properly run a program like this," Bolton told the House International Relations Committee in his first extensive public comments about the United Nations since his recess appointment early last month.

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The Oil-for-Food program, which allowed Iraq to trade fuel for food and medical supplies, was alleged to have spent millions in paying off middlemen along the supply chain. Iraq also spent money earned by the oil sales to try to convince some members of the U.N. Security Council to lift sanctions on the Mideast nation.

Also appearing before the committee was Mark Malloch Brown, Secretary-General Kofi Annan's chief of staff, who stepped into what some at the United Nations consider the lion's den. He escaped without a mauling, instead being treated respectfully by committee members who appear to have made the calculation that he is a genuine reformer who has Annan's ear.

Brown told FOX News in an exclusive interview that the recent U.N. summit was a major step forward on the road to reform in that it gave top officials an endorsement to press ahead with sweeping management changes that might prevent another Oil-for-Food type scandal in the future.

Asked why Annan needed an endorsement for reform, Brown said Annan has to operate like most heads of democratic states.

"You ask the president of the U.S. or the prime minister of Britain if they can do everything they want, working with a Congress or a parliament ... and in the case of the U.N., the Congress has trampled all over the freedom of the secretary-general to manage," Brown said.

Brown said Annan did not step aside, even though he was personally damaged in the scandal and has faced other allegations of mismanagement on his watch, because it would only lend credibility to the enemies of reform.

"If he stepped aside, the member nations could just dismiss it as the problems of one man rather than facing the fact that these are systemic institutional failings," Brown told FOX News.

The General Assembly approved a reform plan that had been heavily edited by Bolton to remove statements that appeared to reduce the sense of global disapproval of terrorist acts and demanded more concrete U.N. reforms. Bolton said the reforms are watered down but he voted yes despite reservations.

"We didn't get everything we wanted, but we made progress," Bolton told the committee.

He offered a checklist of requirements for U.N. management that were part of the document the world body approved, and said the United States will not stop there.

Bolton told congressional members that reforms should be carried out urgently so that momentum is not lost.

Despite Bolton's misgivings, the House International Relations Committee also put the United Nations on notice that it intends to push ahead with Chairman Henry Hyde's reform resolution, passed by the House earlier this year, which calls for the withholding U.S. dues unless the United Nations takes specific measures to fix those failings. The Senate has not advanced a similar measure.

Bolton said the Bush administration opposes the bill.

"I've been an executive branch official my entire public career and, for both constitutional and historical reasons, the executive branch appropriately has typically opposed automatic, non-discretionary directions from all of you esteemed ladies and gentlemen," Bolton said. "That's our position. I support it emphatically."

The Associated Press contributed to this report.

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