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• Annan informed about reports
• U.N. reassessing its role in Iraq
• Pressure on Butler
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UNITED NATIONS (CNN) -- Chief U.N. weapons inspector Richard Butler on Wednesday denied reports that his teams were used to monitor sensitive Iraqi communications in a U.S. effort to undermine Iraqi President Saddam Hussein.

Butler was asked about a Washington Post story saying UNSCOM -- the U.N. special commission in charge of dismantling and monitoring Iraq's weapons of mass destruction -- had provided aid to U.S. intelligence operatives.

"I've said in public that it's simply untrue," Butler said, adding that he would comment further Wednesday afternoon.

The Boston Globe and The Washington Post -- citing anonymous sources -- said an electronic eavesdropping operation allowed U.S. intelligence agents to gather secret communications among military units guarding Hussein.

The Washington Post said U.N. Secretary-General Kofi Annan had convincing evidence that U.N. arms inspectors helped collect eavesdropping intelligence used in U.S. efforts to undermine the Iraqi regime.

The Boston Globe reported that U.S. intelligence agents were able to listen in on secret communications between elite military units responsible for Hussein's security.

A White House spokesman refused to comment on "intelligence matters," noting only that the United States was one of the member states in the United Nations providing support to the U.N. arms inspectors in Iraq. A State Department spokeswoman also declined to comment.

Annan

The Post quoted unnamed confidants close to Annan as saying he had learned that UNSCOM helped Washington listen to some of Iraq's most sensitive communications.

Annan had received classified U.S. intelligence, passed to him through intermediaries, about the eavesdropping activities, the Post said.

The sources acknowledged that the eavesdropping was aimed in part at helping the inspectors hunt down forbidden weapons, or the means to conceal them, but told the Post that Annan was convinced that Washington used the operation to penetrate the security apparatus protecting the Iraqi president.

"The secretary-general has become aware of the fact that UNSCOM directly facilitated the creation of an intelligence collection system for the United States in violation of its mandate," the Post quoted one Annan adviser as saying.

"The United Nations cannot be party to an operation to overthrow one of its member states. In the most fundamental way, that is what's wrong with the UNSCOM operation," the source was quoted as saying.

The United Nations has been reassessing what role UNSCOM has to play in Iraq after U.S. and British airstrikes against the country last month. In the wake of those airstrikes, Baghdad said that the arms inspections had been terminated.

The latest revelations will likely heighten Iraq's suspicions about the commission and make it less likely that any arms inspectors will be allowed back in.

UNSCOM was created by the U.N. Security Council after the 1991 Gulf War. The commission withdrew all its personnel before the December 16-19 U.S. and British airstrikes.

Iraq has repeatedly accused UNSCOM of spying for the United Sates, rather than following its U.N. disarmament mandate.

The Boston Globe, citing information from unnamed U.S. and U.N. officials, said the plan to penetrate Iraq's intelligence apparatus was believed to be ongoing.

It said it was unclear if the operation, which it said began in February 1996, was designed to topple the Baghdad regime.

The Globe said U.S. officials "privately acknowledged that they were engaged in the operation."

The Post said Annan's advisers acknowledged that the secretary-general was trying to put pressure on Butler to resign in favor of a successor who might win the consent of Iraq and its defenders on the Security Council.

The paper quoted Assistant Secretary-General John Ruggie as saying that if the allegations were proven true, "they would pose a serious challenge for the United Nations with regards to our disarmament work in Iraq and multilateral arms control efforts generally."

The Associated Press and Reuters contributed to this report.