WASHINGTON, Jan. 6 -- United States officials said today that American spies had worked undercover on teams of United Nations arms inspectors ferreting out secret Iraqi weapons programs.

Iraq has long condemned the inspectors as tools of American intelligence. In October it issued a statement saying it would never cooperate with United Nations teams riddled with ''American spies and agents.''

United States officials said American intelligence agencies provided information and technology to the United Nations Special Commission, known as Unscom. In turn, they said, the United States and other nations received information on Iraqi weapons programs from the inspectors.

By being part of the team, the Americans gained a first-hand knowledge of the investigation and a protected presence inside Baghdad.

Intelligence-gathering devices supplied to the inspectors by Washington gave the United States a better understanding of the sites at which Iraq developed and concealed weapons of mass destruction, American officials said.

The commission has been a unique attempt by the United Nations to establish an international intelligence-gathering and analysis operation. Its mission was to uncover Iraqi weapons programs that continued after the 1991 Persian Gulf war.

Scientists, military officers, diplomats and other professionals serve on the commission. The United States included some intelligence officers, using diplomatic cover or other professional identities, to gather intelligence independently, according to the officials.

American officials did not say how many spies served on the commission or describe their roles.

The disclosure that American spies had worked as inspectors came after The Boston Globe reported today that such agents had used the team as a cover to spy on President Saddam Hussein.

The Washington Post also reported today that the commission had worked with American spy agencies to gain intelligence that was used to undermine the Iraqi leader.

American officials also said today that a former American United Nations inspector was misinformed when he said the United States had taken over a United Nations intelligence operation in Iraq.

American officials said that while the United States had participated in the United Nations teams' intelligence-gathering operation, they had not taken it over. They strongly rejected reports that the teams had been used as a tool of American intelligence, as did Secretary General Kofi Annan and the commission's current and former chairmen.

''We not only have no convincing evidence of these allegations,'' said Fred Eckhard, the spokesman for Mr. Annan, ''we have no evidence of any kind.''

A senior Administration official said: ''Unscom does not have an indigenous intelligence capability; that was provided by member states. The information it gathered was used to help break Saddam's concealment effort, and the information was passed on to United Nations Security Council members.''

In an interview, Scott Ritter, a former United States Marine intelligence officer, raised the question of whether the inspectors improperly aided United States intelligence in ways that threatened the inspectors' independence, or opened them up to charges of spying for Washington.

American officials said today that Mr. Ritter was describing a secret United States-assisted United Nations intelligence program that he did not fully understand.

Mr. Ritter said the inspectors had developed ''methodologies,'' which he refused to describe, that helped them understand how Iraqi security services concealed arms programs. The same security services and methods of concealment were also used to protect Mr. Hussein, he said.

Mr. Ritter said his inspection team ''had a tremendous success using these methodologies'' in March. A few weeks later, he said, American officials approached Richard Butler, an Australian who is chairman of the United Nations commission.

''In April, the U.S. went to Butler and wanted to take over a certain portion of the system of how we track these weapons,'' he said. ''I wanted to make sure it was only for tracking weapons, but the U.S. wanted to cut me out.

''I could no longer guarantee that the methodology would be used'' for weapons inspections alone, and not to benefit United States military and intelligence agencies, he said.

''Butler will have to convince people that what the U.S. did was for Unscom,'' said Mr. Ritter. ''I think we were given assurances the information would not be misused,'' he said. But, he added, he believed that the United States ''used Butler.''

''I think they set him up,'' he said.

Mr. Ritter resigned in August, saying the United States and the United Nations had undermined the inspectors.

A Government official familiar with the dispute said Mr. Ritter was ill-informed, explaining that there had been a shift in the commission's intelligence-gathering methods last spring.

''There was a period when Mr. Ritter was familiar with these methods,'' the official said. ''The methods have since gotten better, but Mr. Ritter wasn't totally witting of what was done.''

And a White House official lashed out at Mr. Ritter today, saying his allegations had delivered a pointless propaganda victory to Iraq.

Mr. Butler said the commission had asked for more advanced technology after discovering in 1995 the sophisticated lies and methods of concealment that Iraq had used to hide its weapons programs and missile projects.

''I want to say this with all the force that I can: We have never accepted or used any of that assistance for any other purpose'' than disarming Iraq, Mr. Butler said.

''Have we facilitated spying?'' he said. ''Are we spies? Absolutely not.''

Mr. Butler's predecessor, Rolf Ekeus, now Sweden's Ambassador to the United States, said the teams had ''exclusively devoted their activities in Iraq to identifying Iraq's holdings of weapons of mass destruction.''

In an interview, Mr. Ekeus also said no eavesdropping equipment had been installed by the United States to spy on President Hussein or on the troops who protect him. Mr. Butler also denied that any such eavesdropping took place.

Monitoring the efforts of Iraq's Special Republican Guard and Special Security Services to conceal clandestine weapons programs might have led to Iraqi protests that these troops were being spied on.

The inspectors were withdrawn in December, hours before American and British attacks on Iraq. Mr. Hussein has said they will not be allowed to return unless the Special Commission is restructured and Mr. Butler is replaced.

Some United Nations diplomats and officials say Mr. Butler's position may be stronger now because officials have been forced to rally publicly behind him.

Mr. Annan was reported to be particularly enraged by assertions from unnamed sources quoted by The Washington Post who said he was suspicious of Mr. Butler and the commission.

Mr. Eckhard also said the Secretary General, who has sometimes been critical of Mr. Butler's blunt style, was not putting pressure on Mr. Butler to resign.

Copyright 1999 The New York Times Company

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