Updated

The United States suspended U-2 surveillance flights over Iraq Tuesday after Iraq threatened two of the American spy planes, forcing them to abort their missions and return to base, senior U.S. officials said.

The officials stopped short of saying the Iraqis threatened to shoot down the aircraft.

A Pentagon official said the decision to end the mission was made "in the interest of safety."

In Baghdad, Iraqi officials said the aerial confrontation was a "technical mistake" resulting from a mistake on the part of U.N. weapons inspectors, who the Iraqis said have apologized to Iraq.

Maj. Gen. Hossam Mohammed Amin, the chief Iraqi liaison with U.N. weapons inspectors, told reporters that the second flight by the American U-2 had not been scheduled.

He said both flights took place Tuesday morning and it was the U.N. inspectors who ordered the two planes to leave Iraqi airspace.

Amin said the second plane's entry point was over the Iraqi-Saudi border and not from Kuwait, as has been the custom since the flights began last month.

He said he contacted the senior U.N. inspector in Baghdad, who told him that a technical error was made. "He promised that the mistake would never be repeated and offered his sincere apology," Amin said.

The U-2 planes were flying missions at 2 a.m. Iraqi time for the U.N. weapons inspectors when Iraq launched fighter jets. According to two U.S. officials, a threat was directed against one of the two planes.

One U.S. official said the Iraqi threat on the U-2s was fresh evidence of Baghdad's unwillingness to cooperate with U.N. inspectors.

Amin poured scorn on the American version of events, saying it reflected "the frustration and the failure of American policies in finding excuses for aggression against Iraq."

Ewen Buchanan, a spokesman for UNMOVIC, the U.N. inspection agency, said in New York that Iraqi authorities "expressed surprise" when notified of the flights and the agency requested the planes turn back. Further U-2 and Mirage reconnaissance fights are planned, he said.

"I can confirm that two U-2 reconnaissance aircraft operating on behalf of UNMOVIC operated in Iraqi airspace this morning. Although Iraq had been notified of a flight time window, they expressed surprise and concern that two flights were operating simultaneously. In the interest of safety UNMOVIC requested the aircraft to withdraw. Further U-2 and Mirage reconnaissance flights are still planned."

The statement made no reference to Iraq launching fighter jets, nor was it critical of Baghdad in any way.

Multiple flights are permitted under a U.N. Security Council resolution approved last November, and the Bush administration sought clarification from U.N. inspectors after the U-2 flights were suspended.

A senior U.S. official said the U-2 flights that were diverted were the seventh and eighth sent on a surveillance assignment since the Security Council approved the resolution unanimously, and that the flights had been coordinated with the U.N. inspection agency.

But Iraq "raised a fuss," this official said, and the two flights were recalled.

The dispute punctuated a behind-the-scenes effort by the United States and Britain to win support for a new resolution designed to back the use of force as a last resort to disarm Iraq.

U-2 flights are conducted as part of an elaborate inspection arrangement designed to determine whether Saddam Hussein has secretly stored chemical and biological weapons in defiance of U.N. resolutions.

Typically, Iraq is notified in advance of overflights of Iraqi territory.

The Associated Press contributed to this report.