Officials declined to specify what findings David Kay might include in his upcoming report but said Wednesday it is not expected to reach any conclusions about Iraq's alleged weapons program.
A CIA official tells CBS News White House Correspondent Peter Maer that the findings from Kay are only "an interim progress report."
U.S. and British officials have not disclosed any discoveries that would validate their prewar assertions that Iraq had weapons of mass destruction ready to use.
Kay, a former U.N. weapons inspector, is the CIA adviser working with teams in Iraq searching for evidence of chemical and biological weapons, programs to make more, and prohibited missiles and nuclear weapons programs.
Some Pentagon officials, speaking on the condition of anonymity, have said that weapons hunters have found what they interpret as evidence of Iraqi preparations to secretly produce chemical and biological weapons.
That evidence is primarily drawn from documents and interviews with Iraqi officials, the officials said. It suggests plans for weapons production that was to take place primarily at "dual-use" manufacturing facilities inside Iraq, the U.S. officials said.
These are buildings with an overt, legitimate purpose, such as making pesticides or pharmaceuticals, but their equipment also can be used to make weapons.
The officials did not know whether searchers had found any evidence that weapons production had actually taken place at these sites.
The BBC reports Kay's interim study will conclude it is "highly unlikely" that weapons were shipped out of Iraq before the war. Early in the weapons hunt, some U.S. officials that Saddam Hussein may have sent his suspected stockpiles to Syria.
Kay is expected to present his findings to CIA Director George J. Tenet and other officials soon.
"Dr. Kay is still receiving information from the field, and this will be just the first progress report, an interim report, and we expect it will reach no firm conclusions, nor will it rule anything in or out," said CIA spokesman Bill Harlow.
He said it has not been determined how much, if any, of Kay's report would be made public. After the interim report is complete, Kay is expected to return to Iraq to continue his investigation.
News, "If there were going to be something that was going to be found it would have been found already."
In August, Kay suggested a breakthrough was close but added that the U.S. government would proceed slowly before going public with any discoveries, to make sure its analysis was sound.
With the cost of the Iraq invasion in lives and dollars increasing, the Bush administration and its top ally, British Prime Minister Tony Blair, have been under pressure to prove their claims that Iraq's weapons of mass destruction posed an imminent threat.
As the weapons hunt has turned up empty, those allegations about Iraq's arsenal have been eroded. Claims about smallpox, unmanned aerial vehicles, and uranium purchases from Niger have been discredited. There is disagreement on whether two trailers found in northern Iraq were mobile biological weapons labs.
U.S. officials suspect that some of the intelligence used to justify the war against Iraq came from defectors who were lying or reporting false information planted by Saddam 's regime, The Los Angeles Times reports. Some former weapons inspectors believe many of the suspicions about Iraq's alleged stockpiles may be because of bad bookkeeping in Baghdad.
Administration officials in recent days had sought to lower expectations that Kay's report would put to rest ongoing questions about whether Iraq had prohibited weapons and programs.
On Fox News Channel on Wednesday, national security adviser Condoleezza Rice said: "David Kay has miles of documents to go through. He has hundreds of people to interview. … He's going to put together the picture."
"I await the report eagerly from Mr. Kay as does the international community," said British Foreign Secretary Jack Straw at the U.N. General Assembly on Wednesday.
In his speech to the United Nations on Tuesday, Mr. Bush insisted Iraq had posed a threat.
"The regime of Saddam Hussein cultivated ties to terror while it built weapons of mass destruction. It used those weapons in acts of mass murder, and refused to account for them when confronted by the world," the president said.
But war opponents and some Democrats are pointing to a remark by Secretary of State Colin Powell in February 2001.
Visiting Egypt, Powell told reporters: "(Saddam Hussein) has not developed any significant capability with respect to weapons of mass destruction. He is unable to project conventional power against his neighbors." Powell also insisted the sanctions regime was working.