U.S., Britain Warn Iraq Against Buildups : Mideast: Diplomatic notes detail U.N. resolution terms. Administration cancels deployment of 23,000 troops.

The United States and Britain formally warned Iraq on Thursday not to deploy additional forces near the Kuwaiti border and said the West will launch massive air strikes if Iraqi troops cross a specific line.

The warning came in separate diplomatic notes handed to Iraqi U.N. Ambassador Nizar Hamdoun and designed to spell out the terms of a broader resolution on Iraq that the United Nations Security Council passed Saturday.

U.S. officials said the statements prohibit Baghdad from keeping any more troops below the 32nd Parallel than it had there Sept. 20, before its latest buildup. That limits the Iraqis to just over six small divisions--none of them elite Republican Guards.

Pentagon officials said Thursday that most of the two Republican Guard divisions that Iraq sent to the Kuwaiti border between Oct. 6 and Oct. 11 had retreated above the 32nd Parallel, reducing force levels near the border to about what they had been before the buildup.

Completion of the Iraqi troop withdrawal essentially ended the two-week confrontation between Iraq and the Western allies. The retreat came after the United States began deploying a sizable force of troops and aircraft to deter an Iraqi invasion of Kuwait.

As has been expected for days, the Clinton Administration marked the Iraqi withdrawal by canceling the scheduled deployment of about 23,000 U.S. ground troops--including 18,000 Marines from the 1st Marine Expeditionary Force at Camp Pendleton.

U.S. officials said that 13,000 American combat troops in the Kuwait area or on their way will stay in the region for military exercises, probably lasting several weeks. If the situation remains quiet, they will be brought home.

Military officials said that, at the height of the recent crisis, Iraq had amassed 70,000 to 75,000 troops between the 32nd Parallel and the Kuwaiti border--including two Republican Guard divisions, 1,090 tanks, 970 armored vehicles and 670 artillery pieces.

Although the United States moved quickly to pour ships, planes and troops into the area, there was a “critical window” between Oct. 9 and 10 when the Iraqis could have invaded and allied resistance “would not have been enough to deter them,” the officials said.

Air Force Lt. Gen. Howell M. Estes III, the new operations director for the Joint Chiefs of Staff, told reporters that “based on the intelligence we are seeing now in Iraq, we obviously can see that the threat is receding. . . . But clearly (it) is not totally eliminated.”

As a result, officials said, Washington will continue to keep troops in the area and use the opportunity to test a new quick-deployment procedure under which combat units sent from the United States would be paired with weapons and equipment kept permanently at sea in cargo ships.

The United States has deployed 274 aircraft, about half of them fighters or bombers, to the region, as well as an aircraft carrier, five missile-carrying warships and an amphibious group that includes Marines.

Thursday’s order also cancels deployments of the 101st Air Assault Group of Ft. Campbell, Ky., and the 1st Cavalry of Ft. Riley, Kan., as well as six B-52 bombers and a squadron of radar-evading F-117A Stealth fighters.

In all, the Pentagon had earmarked 155,000 troops and 600 aircraft for deployment.

The diplomatic notes delivered to the Iraqis not only barred additional troops below the 32nd Parallel but warned Baghdad against configuring the forces it now has in the region in a way that appears to threaten Kuwait.

A senior European diplomat told reporters in Washington that the documents were needed to ensure that Iraq is given a clear warning and to provide a stronger legal basis for military action if Baghdad violates the restrictions.

He said that the resolution the U.N. Security Council passed last weekend did not itself provide “a sound legal basis” for launching punitive air strikes. It did not explicitly threaten force because Russia and China had objected.

The 32nd Parallel line specified Thursday by the United States and Britain also is the northern boundary of the “no fly” zone that the allies established in 1992 to prevent Iraqi aircraft from harassing Shiite nomads who live in the country’s southern swamps. U.S. and British aircraft have routinely patrolled the entire region for the last two years.

A senior U.S. military official told reporters Thursday that, although Iraq had withdrawn virtually all its Republican Guard forces from the area, it still has the capability to “regenerate” its forces and once again push close to Kuwait.

“That constitutes, in my view, a continuing threat in the absence of (a) credible deterrent in their eyes,” he said.

Officials said France, which had also differed with the United States over whether to authorize air strikes in enforcing the U.N. resolution, issued a verbal admonition to the Iraqis on Thursday but did not join the United States and Britain in threatening air strikes.

Meisler reported from the United Nations and Pine from Washington. Times staff writer Doyle McManus in Washington contributed to this report.