President Bush's National Security Council is debating whether to turn its most sensitive intelligence on Iraq's chemical and biological weapons programs over to United Nations inspectors or hold some to offer later to the U.N. Security Council as a reason for war, according to senior administration officials.

Adding to the complexity of the discussions are Pentagon officials who want to withhold intelligence on Saddam Hussein's alleged weapons sites because they would be among the first targets for the United States should an attack take place, the officials said. Disclosing the locations of these weapons would inevitably lead to their being moved, the military targeters said.

At issue is the best way to use U.S. intelligence to convince Security Council members and the world that Hussein has chemical and biological weapons, especially since U.N. inspectors so far have failed to uncover any "smoking gun."

U.S. officials have said that omissions in Baghdad's December declaration of its weapons of mass destruction mean Iraq remains in material breach of U.N. resolutions calling for it to disarm. But the White House has recognized it needs evidence of Hussein's weapons or an open obstruction of the inspectors before it can put together a coalition for military action, senior officials said.

A key issue in the internal White House debate is releasing intelligence that could endanger either the human spies or technical collection systems that originally obtained the information. "It all comes down to weighing revealing sources and methods versus making a public case," a senior administration official said yesterday.

Two weeks ago, this official said, "everybody started saying that we should 'do an Adlai Stevenson,' " a reference to the Kennedy administration's U.N. ambassador showing aerial reconnaissance photographs to the Security Council in 1962 to prove Soviet missiles were being put in Cuba.

"Maybe that will be the answer," the Bush official said, "[maybe] at some point, protection of sources and methods will be outweighed by the need to convince the American public, the British Labor Party and the people in Turkey that there's a very, very strong case out there."

"The White House is trying to decide what to lay out to inspectors before they report on January 27 or whether to wait and do it after," another official said yesterday. "If we then go forward [attacking Iraq], the question also is how much leg do you show ahead of time," the official added.

Secretary of State Colin L. Powell said this week that the United States has begun delivering some intelligence to the inspectors and is reviewing other more sensitive material with an eye toward presenting it to the Security Council if inspections fail to uncover a smoking gun. One senior official familiar with U.S. intelligence said recently that the quality of U.S. data "is not that good," adding, "I don't expect anything dramatic before January 27."

Defense Secretary Donald H. Rumsfeld discussed the intelligence dilemma earlier this week, telling reporters it would eventually have to be settled by Bush. "I think he would probably make a calculation as to the advantages that would accrue from revealing intelligence information and the disadvantages that would result from doing so," Rumsfeld told reporters Tuesday.

"On the one hand you have the advantage of persuading the public and the world and countries of the facts of the matter," he said. On the other hand, he said, "To the extent that prior to using force we were to reveal intelligence information in a way that damaged the ability to conduct the conflict, it would be, needless to say, unfortunately risky for the coalition forces' lives engaged."

The U.S. intelligence transferred over the past week has been general in nature but included satellite photos of some suspected storage sites, according to former inspectors familiar with the current system. Only Hans Blix, executive director of the U.N. Monitoring, Verification and Inspection Commission and his top intelligence assistant, the former deputy head of Canada's intelligence service, James Corcoran, initially review the data. It is then turned into orders passed on to field inspectors in Iraq who do not know its origins.

Sensitivity of the information has slowly increased as the security of the system has been tested. It has remained general and the internal administration debate will determine how specific future sensitive information will be.

Illustrating the problem was the complaint yesterday by one of the two chief inspectors that he needed "more actionable information" from U.S. intelligence agencies. Director General Mohamed ElBaradei of the International Atomic Energy Agency, who supervises the search in Iraq for a nuclear weapons program, told reporters, "We need specific information on where to go and where to inspect."

He said a good process has been established with the United States and other countries' intelligence agencies and he hoped that in coming weeks "we'll get additional information that can accelerate our job in the field."

Asked about ElBaradei's remarks, State Department spokesman Richard A. Boucher said, "I can certainly say that they're getting the best we've got, and that we are sharing information with the inspectors that they can use, and based on their ability to use it."

White House press secretary Ari Fleischer yesterday added the need to protect security of data as another reason for limiting the sensitive U.S. information being given the U.N. inspectors.

"The more secure their ability is to maintain the information, as new equipment arrives to help them to do so, the more information they receive," he said, adding that Iraq in the past has used its abilities to intercept messages and stay one jump ahead of the U.N. personnel.