Millions of dollars have been approved and thousands of recruits have been listed on a roster, but the Pentagon is still pondering exactly how to use Iraqi nationals who want to help overthrow Saddam Hussein.

"There are probably more unknowns than there are knowns right now,'' said Gen. Richard Myers, chairman of the Joint Chiefs of Staff.

Overall, officials see more pluses than minuses in the idea of being accompanied in any Iraq campaign by men who know the language, territory and culture.

But still undecided, several Defense Department officials said Wednesday, is whether the men would best be used as fighters or battlefield helpers. It appears they are leaning toward them being mostly helpers.

They also are working on pinning down the who, what, when and where details of any training program. Until a group of recruits is assembled and their skills evaluated, it's uncertain whether they'll be of more use before Saddam is overthrown or in a transition period after, two defense officials said.

Under a directive signed early this month by President Bush, the Pentagon can use $92 million to train and equip Saddam's opponents. The money was provided in the 1998 Iraq Liberation Act, which called for toppling Saddam's regime.

Only about $5 million has been spent, partly because of uncertainty about the effectiveness of the Iraqi National Congress, an opposition umbrella organization. The White House and the Pentagon have recently shown far more interest in dealing with the group as the administration plans to oust Saddam.

Over recent months, the Pentagon has gathered the names of several thousand possible trainees — men nominated by the London-based INC as well as other Saddam opponents, defense officials said Wednesday on condition of anonymity.

More than 1,000 have been through preliminary screening, mostly trying to make sure they are not on lists of criminals or Saddam loyalists, a U.S. official said.

An eventual force of 3,000 to 5,000 men is envisioned by some officials. Others would like to see as many as 10,000 assembled and trained, a feat that could take more time than is practical.

"We're in the preliminary stages of trying to determine if there are people out there that might be helpful in case the president asks us to use force in Iraq,'' Myers told a Pentagon news conference Tuesday.

Asked what jobs they would be trained to do, Myers said it depends on "the sort of people you get and what you want them to do.''

Until the men are assembled and their skills known, officials won't know exactly what they are capable of and willing to do, three defense officials said. But the main jobs being considered so far include language translators, battlefield advisers, liaisons between the military and local population, scouts, guards for any prisoner-of-war camps that could be set up in Iraq and officers to assist in peacekeeping or other transition tasks between the time Saddam is overthrown and a new government is up and running.

"It makes perfect sense,'' said Laith Kubba, an Iraqi at the National Endowment for Democracy. "If there were to be operations, you need to have people who know the local dialect, who know issues, names, who can help an army if they want to move.''

He cautioned that care must be taken to assure training doesn't strengthen the hand — or amount to the arming — of one faction over the other among Iraqi opposition groups.

During the Clinton administration, some 140 Iraqis received limited training at military schools in Texas, Rhode Island and elsewhere. Subjects included emergency medical techniques, logistics, warehouse management and communications or public affairs skills.

Officials said it could be a couple of weeks before any plan for military training is finalized and at least a month before the men might be taken somewhere for the training.

The program could potentially bring Iraqis from around the world — including exiles and those still inside Iraq — to assist in various phases of the effort, officials said.

It has been estimated that there are well over 3 million Iraqis in exile, the largest groups in Jordan and Iran, with a few hundred thousand in the United States.

Asked Tuesday where the Pentagon is looking for recruits, Defense Secretary Donald H. Rumsfeld said, "Wherever Iraqis are.''