Iraq has complained to the United Nations about a plan to use American spy planes to aid inspectors' search for illicit weapons, the top U.S. military officer said Wednesday.

Gen. Richard Myers, chairman of the Joint Chiefs of Staff, told a Pentagon news conference that the Bush administration had offered U-2s, which provide high-altitude surveillance, and Predator unmanned aircraft, which fly low and send live television images of surveillance targets to command posts on the ground.

So far the U.N.'s inspection arm has accepted only the offer of U-2s, Myers said, although none have flown yet.

"We're ready to go whenever they're ready to go," Myers said.

Myers said the Iraqi government had sent a letter to Hans Blix, the chief U.N. weapons inspector, complaining about the U-2 arrangement.

The Iraqis told Blix they "have a real problem with U-2s flying over central Iraq" because it would complicate the Iraqi air defense forces' mission of defending against U.S. and British fighter jets that periodically attack Iraqi military sites in the southern and northern no-fly zones, which do not include the Baghdad area.

Defense Secretary Donald H. Rumsfeld, appearing with Myers, said that was a poor argument because the U.N. Security Council resolution under which the weapons inspections are authorized says the Iraqis may not interfere with patrols over the no-fly zones.

Iraq does not recognize the legality of the no-fly zones and says it considers the U.S. and British fighter patrols to be violations of Iraqi sovereignty.

Blix reminded the Iraqis that inspectors had said in October that they retained the option of using U-2s for high-altitude aerial surveillance. He told Iraq it had an obligation to ensure the safety of such operations, said Ewen Buchanan, Blix's spokesman.

Myers did not say where the U-2s would be based. The planes, which would be flown with U.N. markings, have a long and storied record of high-altitude surveillance dating to the 1950s, when the United States wanted to discover the extent of the Soviet Union's strategic offensive capabilities before spy satellites were available. They also played a role in the 1962 Cuban missile crisis with the Soviet Union.

Meanwhile, Iraqi exiles who want to help the American military depose President Saddam Hussein are beginning to report for training.

The Pentagon said Wednesday that the first batch of opposition members who've volunteered to serve with U.S. forces have been told to assemble at a secret location in the United States over the next several days.

"The training is going to be ... real basic training so they could potentially fit in with some U.S. units and provide assistance with language skills, perhaps, or local knowledge and so forth," Myers said.

The assembling of recruits kicks off the largest known U.S. effort to train Saddam's enemies since passage of the 1998 Iraq Liberation Act, which called for his overthrow and authorized $97 million to train and equip his opponents.

The Joint Chiefs chairman also warned Saddam not to carry out any plan to recruit civilians to act as human shields during a U.S.-led aerial attack.

Such a shielding effort would be considered a war crime, he said.

Asked how U.S. troops would respond if faced with human shields, Myers said, "I think there will be some situations where military necessity, if it's a case of defending the friendly forces, that you'd have to take action probably. And there are other cases where if you can avoid it you would, of course. You know the object is clearly to not engage noncombatants."

Myers will be traveling to Europe next week, including a visit to Turkey. The United States is trying to secure the use of military bases in Turkey in the event of a war with Iraq.

On other subjects, Rumsfeld said:

-- It should not be surprising that many Americans are still asking why the United States might attack Iraq.

"The president has not made a case for going to war because he has not made such a decision," he said. "So one ought not to be surprised that, in fact, there are people who look at the situation and may come to a conclusion that that case hasn't been made at this point. And I think that's a fair comment."

-- Congress should move swiftly to provide emergency funds for the Pentagon to pay for its large buildup of forces in the Persian Gulf region. He said Congress' inaction has forced the Pentagon to take money from elsewhere in its budget to meet the deployment costs.

"We're robbing Peter to pay Paul. It's a terrible way to manage your affairs," he said.