Updated

Former Iraqi Vice Premier Tariq Aziz (search), who surrendered to U.S. authorities on May 24, has been providing considerable information about Saddam Hussein, officials familiar with his interrogation told Fox News.

Aziz, the highest-ranking Iraqi Christian in Saddam's regime, was initially close-lipped, several Pentagon and U.S. officials said. But once his family was moved out of the country to safety, he is said to have begun talking at length.

"That made a night and day difference," one source said.

Compounding Aziz's information, U.S. intelligence agencies have been going over millions of documents — 9½ miles' worth if laid end to end — left behind by Saddam's government after its sudden collapse around April 10.

The stories were both first reported Monday in The Washington Post and The Wall Street Journal.

Among the details provided by Aziz and the captured files:

— Saddam did not attack invading American and British forces because he believed that France and Russia would use the U.N. Security Council to stop the war.

— Ties were even stronger to two other nations: North Korea, which was in the process of selling Iraq a long-range No Dong missile, and Serbia, which provided Iraq with a sort of "lessons learned" template from its experience in dealing with the NATO-led air campaign over Kosovo.

— Iraq had no biological, chemical or nuclear weapons, according to Aziz, an assertion echoed by most other captured Iraqi leaders. But Saddam was insistent on developing long-range missiles despite the U.N. resolution barring him from doing so.

— The names of every Iraqi intelligence agent working abroad over the past few years. "We know [Saddam] had agents all over the world. We know who they are, and we're going to find all of them," one official told Fox News. "The Iraqis were meticulous record keepers."

Serb-Iraqi contacts were military-to-military, the officials said, and the Serbs gave many tips on enduring a prolonged air campaign, the officials told Fox News.

That information, measured against Iraq's own experience against the massive air campaign in the first Gulf War, led Saddam to believe the allies would strike this time with a sustained air campaign, and that he could ride it out.

Aziz said he argued with Saddam at length about the missile restriction, the Post reported. Saddam seemed to believe the U.N. prohibited missiles with a range of more than 150 kilometers (93 miles) only if they were carrying nuclear, chemical or biological warheads.

Aziz said he countered, "No, it's a range limit," according to the Post. Saddam demanded in reply, "No, I want to go ahead."

According to Aziz, Saddam was worried that neighboring countries — especially Iran — would be able to strike at Iraq without fear of even conventional retaliation.

Paradoxically, Saddam counted on the Americans to keep Iran's own nuclear, chemical or biological weapons aspirations in check, Aziz said.

"Every time I brought up the issue with Saddam, he said, 'Don't worry about the Iranians. If they ever get WMD, the Americans and Israelis will destroy them,'" the Post quotes Aziz as saying.

U.S. officials were quick to point out that Aziz, as someone skilled at the art of spin and deflection, may not be telling the entire truth.

The officials also point out that Aziz, Iraq's foreign minister during the 1991 Gulf War, had fallen out of favor in recent years and held the mostly ceremonial post of deputy prime minister.

Maj. Gen. Amer Shia Jubouri, a former Iraqi army commander, said in to the Post that he believed "the French and Russian governments delivered very clear messages to Saddam that the war was going to happen," and that if Hussein believed otherwise, it was a result of the president's own confusion.

"He obviously misunderstood the theory of deterrence," said Jubouri. "You have to know when this theory can be successful, and when it can be disastrous."

The captured Iraqi papers number "almost as much as the Stasi files," one senior U.S. official told the Post, referring to the avalanche of documents from the East German intelligence service, which passed into Western hands during the Eastern Bloc collapse in 1989.

The documents not only name nearly every Iraqi intelligence officer, the Post was told, but also paid foreign agents. Also included are written agent reports, agent evaluations and evidence of influence-buying payments in the Arab world and elsewhere.

The Post reports that other top Iraqi officials have been telling interrogators that although Saddam had no weapons of mass destruction, he wanted everyone to believe he did.

Saddam "had an inferiority complex," said Maj. Gen. Walid Mohammed Taiee, 62, chief of army logistics until the war. "From a military point of view, if you did have a special weapon, you should keep it secret to achieve tactical surprise. ... But he wanted the whole region to look at him as a grand leader. And during the period when the Americans were massing troops in Kuwait, he wanted to deter the prospect of war."

France and Russia opposed the U.S. and British invasion of Iraq. But Russia characterized its contacts with Saddam as an effort to convince him the Americans were serious about invading and that he should abdicate. It is unclear what contacts, if any, the French government had with Saddam.

Saddam's regular army and Republican Guard (search) fought below already low expectations during the war, and intelligence and military officials attributed that in part to poor coordination and communication between units.

Saddam may have thought he would be subjected to airstrikes, instead of an invasion, similar to U.S. attacks in 1998, the U.S. official said.

In early May, President Bush said Aziz, who once served as the public face of Saddam's regime, "doesn't know how to tell the truth." U.S. officials say he has since opened up to interrogators after they arranged for his family to move out of Iraq.

Fox News' Bret Baier, Ian McCaleb, Paul Wagenseil and The Associated Press contributed to this report.