The Bush administration is considering paying for construction of a radio transmitter in either the Kurdish area of Iraq or in Iran as a propaganda tool to weaken President Saddam Hussein's government, the State Department said Thursday.

The two locations are obvious choices because of their proximity to Baghdad.

A senior official, asking not to be identified, said any discussions on the possibility of an Iran-based transmitter would have to take place between Iran and the Iraqi National Congress, an Iraqi opposition umbrella group.

The official noted that the United States and Iran have not had official discussions on political issues for more than 20 years.

Even though President Bush has included Iran in his list of "axis of evil" countries, the two countries share a hostility toward Iraq.

The Iraqi National Congress maintains contact with Iran and sees that country as an ally in its quest to dislodge Saddam from power.

State Department spokesman Richard Boucher said: "We have been in discussions for some time with the Iraqi National Congress regarding a proposal to build a radio transmitter in the region for broadcasting inside Iraq.

"Though we are open to the concept of broadcasting from inside Iran or from Kurdish-controlled areas of Iraq, no decisions have been made on this as yet."

The Kurdish area of northern Iraq has been beyond Saddam's control for years. U.S. and British overflights of the area are designed to prevent Saddam from using his air force to recapture sovereignty over the area.

On Thursday, U.S. military officials reported that Iraqi forces north of Mosul in northern Iraq fired anti-aircraft artillery at allied planes in the no-fly zone, but they were not hit.

"Our pilots were fired upon and we responded by taking out some of their air defense sites," Air Force Gen. Joseph Ralston said, speaking of the incident while testifying on Capitol Hill.

It is not clear whether Iraqi Kurdish leaders, split into two factions that are often at odds, would support the installation of a transmitter on their territory.

They are opposed to Saddam but are not all that displeased with the status quo because they have a measure of autonomy for the first time. A transmitter used to broadcast anti-Saddam propaganda could increase the threat level from Baghdad.

The New York Times was the first to report on the options for locating the transmitter.

Support for the Iraqi National Congress is one of a number of ways the United States is bringing pressure to bear on Iraq.

In an appearance Wednesday night at Georgetown University, the U.S. ambassador to the United Nations, John Negroponte, said revised U.N. Security Council sanctions against Iraq are expected to be in place by June 1.

The new approach is designed to increase the flow of civilian goods for ordinary Iraqis while making it more difficult for Saddam to acquire materials for weapons of mass destruction.

Negroponte said the United States and Russia have been able to narrow differences over which dual-use items should be allowed to enter Iraq.

The United States has favored a more restrictive list than Russia.

"We are quite confident we'll reach agreement with the Russians," Negroponte said.