The FBI is investigating an intercepted Iranian message that alleges Iraqi exile leader Ahmed Chalabi told Tehran officials that the United States had broken Iran's secret code, U.S. officials said.

The message alleges Chalabi said he had been told about the code-breaking by a drunken U.S. official, one senior Bush administration official said.

The New York Times reported in today's editions that about six weeks ago, Chalabi told the Baghdad station chief of Iran's Ministry of Intelligence and Security that the United States was reading the communications traffic of the Iranian spy service, one of the most sophisticated in the Middle East.

Rumors about the alleged intercept had been circulating in Washington for weeks, and Chalabi himself brought up the topic during an appearance on NBC's "Meet the Press" on May 23. At that time, he said, "There are intercepts -- anyone who has intercepts, who has information, any documents -- I am prepared to go and face all of this in the United States Congress. . . . These are allegations that are put forward and directed by the CIA."

At that time he denied he ever passed secret information to Iran, a nation President Bush has cited as part of the "axis of evil."

Bill Harlow, a spokesman for the CIA, said last night he would not comment on the matter.

Chalabi, head of the Iraqi National Congress and once a favorite of many Bush administration officials, has fallen out of favor in recent months as he became an unspoken critic of the U.S.-run Coalition Provisional Authority.

An appointed member of the now-dissolved Iraqi Governing Council, he headed up its finance committee and placed supporters in the Ministry of Finance and the Iraq central bank. He also was chairman of the de-Baathification committee, which gave him power over who could get jobs in the new Iraq government.

Chalabi's appointees have been replaced in the government that was announced yesterday in Baghdad. He has no position in the new cabinet.

The first overt sign of his problems came on May 20, when Iraqi police conducted an early morning raid on his party headquarters and left with computers and boxes of documents. The raid was carried out under a warrant from an Iraqi judge, but Americans were on the scene helping to direct the Iraqi police.

Today's edition of the Times disclosed that the newspaper had withheld publication of the story at the request of the U.S. government but yesterday was released from that request. An article by Jane Mayer in the current issue of the New Yorker magazine also discusses the intercept.

Chalabi's relationship with Iranian officials was well known, and he maintained an office in Tehran, which one of his aides said was paid for by U.S. government money. Before last month's raid, the Defense Intelligence Agency cut off the $340,000-a-month payment the INC received for supplying intelligence before and after the U.S. invasion in March 2003.

"Indeed, I have had many meetings with the Iranian government, but we have passed no secret information, no classified documents to them from the United States because principally we are allies of the United States and we do nothing to harm the United States," Chalabi said during the "Meet the Press" interview.

Richard N. Perle, a onetime chairman of the Defense Policy Board under Defense Secretary Donald H. Rumsfeld and a Pentagon official in the Reagan administration, has been a vocal supporter of Chalabi for years. He said yesterday he knew nothing about the FBI investigation and believes the U.S. position in Iraq would have been much better if the administration had listened to Chalabi's advice to put more exiles in power earlier, rather than trying to run the country through the CPA.

Ahmed Chalabi denies telling Iran that the U.S. had broken its code.