Quoting two diplomats, USA Today says the report is a review of seven years of U.N. weapons inspections in Iraq.
It comes more than a month after David Kay, the leader of the U.S. weapons hunt, told Congress he believes "we were almost all wrong" in prewar assessments of Saddam Hussein's alleged arsenals.
Iraq's alleged weapons of mass destruction stockpiles were a major justification for the U.S-led invasion. They were also the rationale for Operation Desert Fox, an intense bombing campaign ordered by the Clinton administration in 1998.
Kay has reported that Iraq had an illegal weapons program, and had illegally concealed weapons-related programs in other areas. But no actual weapons have been found.
The United Nations report will apparently echo what Hans Blix, the former chief weapons inspector, and International Atomic Energy Agency executive director Mohammed ElBaradei, told the Security Council last year in the run up to war.
Both men cast doubt on Bush administration claims that Iraq possessed weapons or had active programs to produce them. The Bush administration said the U.N. inspectors were being duped by Iraqi intelligence.
Now, the Bush administration's case for war is under investigation by a special presidential commission, the House and Senate intelligence committees and internal and external CIA probes. A separate FBI probe is examining forged evidence on alleged Iraqi attempts to buy uranium in Niger. The Justice Department is investigating who leaked the name of a CIA officer married to a former U.S. diplomat who criticized the White House case for war.
In a confidential report in September, ElBaradei said U.N. inspectors found Iraq's nuclear program in disarray and unlikely to be able to support an active effort to build weapons.
"No indication of post-1991 weaponization activities was uncovered in Iraq," that report read.
Blix, as he left his post this summer, became more open in discussing discrepancies. After the mid-1990s, "hardly ever did (inspectors) find hidden weapons," Blix reminded one audience. "What they found was bad accounting."
Blix's inspection team did find that Iraq's Al Samoud missiles violated range restrictions imposed after the Gulf War, and ordered them destroyed. Subsequent searching has pointed to the missile program as the most advanced of Iraq's weapons research, although some of the projects consisted of little more than paper drawings, according to The Washington Post.
In the months since major fighting ended, several theories have emerged to explain why intelligence on Iraq was so far off target. It's possible Saddam was bluffing to try to prevent an attack, or that his own scientists lied to him. Iraqi defectors may have had a motive to embellish what they told U.S. intelligence.
Others note that when U.N. inspectors left Iraq in 1998, the flow of information was curtailed. That meant there was little to offset the working assumption that Saddam would seek new weapons.
The Senate Intelligence Committee has expanded its review of intelligence on Iraq to examine whether the Bush administration accurately described the information it had on Saddam Hussein's weapons.
The committee will examine "whether public statements and reports and testimony regarding Iraq by U.S. government officials (between the 1991 Gulf War and the Iraq War) were substantiated by intelligence information," committee leaders said.
The panel is nearing completion of a report expected to be extremely critical of the intelligence agencies' collection and analysis of prewar intelligence. Since the inquiry began in June, Democrats have insisted that the commission also examine whether the administration distorted intelligence to help build the case for war.
Republicans have refused and both sides have accused the other of using the traditionally bipartisan committee for political purposes.
The expansion of the inquiry is not expected to delay the release of the committee's report. It is not clear how long it will take to review the administration statements or whether a public report would be released before the November election.
In addition to examining public statements, the Senate committee will also review intelligence activities involving the office of Douglas Feith, undersecretary of defense for policy, and intelligence provided by the Iraqi National Congress, the leading exile group.
Democrats have charged that the Office of Special Plans under Feith functioned as a renegade intelligence agency, feeding policy-makers uncorroborated intelligence from the exile group. The Pentagon has said the office was a small operation set up to review intelligence produced by other agencies.
Last month, CIA director George Tenet said his agency's analysts "never said there was an imminent threat."
But there were differences between how classified CIA reports and public presentations described Iraq's capabilities.
For example, the National Intelligence Estimate on Iraq, drafted in October 2002, reveal doubts by some intelligence agencies about the extent of its nuclear program, the purpose of work its on unmanned aircraft, its doctrine for using WMD and the circumstances under which Saddam Hussein might partner with al Qaeda.
Administration officials rarely, if ever, hinted at those doubts.
And when Mr. Bush and aides in January 2003 mentioned an allegation that Iraq had tried to buy uranium in Africa, it flew in the face of repeated efforts by the agency to keep the charge — which was not substantiated — out of the case for war.