The White House said it still expects inspectors to find weapons of mass destruction (searchin Iraq, even though the United States' lead inspector has returned to Washington to deliver a "progress report" that does not identify incontrovertible evidence of an active prewar program.

David Kay, a former U.N. weapons inspector and now head of the Iraq Survey Group (searchleading the hunt, has presented his interim report to CIA Director George Tenet, U.S. officials told Fox News on Wednesday. Officials said the report does not reach any firm conclusions about the status of former ruler Saddam Hussein's WMD program.

"We continue to believe that he possessed weapons of mass destruction, had a weapons of mass destruction program and Dr. Kay is going to pull together a full picture," White House spokesman Scott McClellan said Thursday.

Officials have not said what they expect would be included in a report, but say he still has considerable paperwork to comb through.

"David Kay has miles of documents to go through. He has hundreds of people to interview. ... He's going to put together the picture," National Security Adviser Condoleezza Rice said in an interview Wednesday on "The O'Reilly Factor."

"The president has made it very clear that he wants Dr. Kay to be thorough and pull together a complete picture so we can have the full truth about [Saddam's] weapons of mass destruction and weapons of mass destruction programs," McClellan said.

The United States and Britain made their case for war arguing that Saddam's weapons program was an imminent threat to their national security.

The interim report will not be given to the public, but will be seen by high-ranking officials in the administration and some lawmakers on Capitol Hill.

"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. "I'm not going to comment on drafts I may have or haven't seen. What we are looking for is published reports and they will be made available in due course."

CIA officials said last week that Kay would be returning to the United States, and his report has been highly anticipated. Earlier this year, inspectors uncovered suspected mobile biological weapons labs and parts from Iraq's pre-1991 nuclear program that had been buried in the desert.

U.N. experts say they believe the findings indicate that Iraq was trying to reconstitute its nuclear weapons program after the first Gulf War, but some in the U.S. intelligence community believe the labs were for hydrogen production for weather balloons.

Some Pentagon (search) officials, speaking on the condition of anonymity, have said that weapons hunters have also found "evidence" of Iraqi preparations to secretly produce chemical and biological weapons, including "dual-use" manufacturing facilities that documents and interviews with Iraqi officials indicate were to be used for weapons production.

The facilities look like legitimate factories for making pesticides and pharmaceuticals, but their equipment can also be used for more nefarious purposes. Inspectors have not indicated whether weapons production actually took place at these sites.

Republicans and Democratic lawmakers who went on congressional delegation visits to Iraq this summer also disagree over whether the evidence they saw indicates an effort to proceed with the weapons of mass destruction programs Saddam clearly pursued before the first Gulf War.

Though the results were inconclusive, that doesn't mean that biological and chemical weapons don't exist, but rather that Kay's team has been unable to search all the possible locations where weapons could be hidden, officials said.

"All of the chemicals specified in the Iraq inventory could fit in a backyard swimming pool and there's space for a lot of swimming pools in a country the size of California," one official said.  

Kay's search is "not a frivolous, look until the end of time" affair, the officials said, concluding, "There's no way you can search the hundreds of thousands of pages or documents or the thousands or millions of places in Iraq you can hide stuff."

One intelligence source said the CIA decided to speak out on the coming Kay report to counter "misinformation," including a claim that Kay was giving up the search. In fact, sources said the wide-ranging investigation will continue, and Kay could return.

Fox News' Wendell Goler, Bret Baier and Ian McCaleb and the Associated Press contributed to this report.