BAGHDAD, Iraq - The new American civilian administrator of Iraq arrived Monday to take over the task of piecing this country back together amid a change in key posts responsible for guiding Iraq toward democracy.

"We intend to have a very effective, efficient and well-organized handover," L. Paul Bremer said after arriving at Baghdad International Airport.

Bremer was traveling with Gen. Richard Myers, chairman of the Joint Chiefs of Staff, and the man Bremer is replacing as the senior American civilian in Iraq, retired Army Lt. Gen. Jay Garner.

"General Garner and I are pledged to working very close together," said Bremer. "I don't anticipate any problems with any of the changes that are ongoing."

Bremer's arrival reflects a turn to new leadership at the top as the civilian reconstruction agency makes inroads to restore law and order and government functions, even as many ordinary Iraqis complain about persistent insecurity and the slow pace of resuming basic services like power and water.

"It's a wonderful challenge to help the Iraqi people basically reclaim their country from a despotic regime," said in a tarmac interview minutes after his plane landed in Basra.

He spent a short while in the southern city before flying to Baghdad, where the civilian reconstruction agency is headquartered.

Asked whether he was, in effect, directing a U.S. plan to colonize Iraq, Bremer said: "The coalition did not come to colonize Iraq. We came to overthrow a despotic regime. That we have done. Now our job is to turn and help the Iraqi people regain control of their own destiny."

Attempting to smooth over implications that his replacement of Garner represented a shifting policy, Bremer said in Basra, "I also want to say how proud I am of the work my good friend Jay Garner and the people who are working for him, how proud I am of everything they have done here in the last couple of weeks under extraordinary circumstances."

He said he wanted to "pay public tribute to Jay and all of his people for the great job they have done."

Reacting to reports that Garner would be leaving the country earlier than originally planned, Bremer said, "I certainly intend to work with him in the next weeks here to get a bunch of serious milestones accomplished."

Standing beside Bremer, Garner said the reports that he would be leaving early are "not true."

"What I say we have here is one team, one fight," said Garner. "We'll drive on."

Bremer said former U.S. ambassador Barbara Bodine, who was coordinator for central Iraq, including Baghdad, within the Office of Reconstruction and Humanitarian Assistance, was being reassigned back to Washington by the State Department "for their own reasons."

The New York Times, citing unidentified administration officials, reported in Monday's editions that four other officials under Garner were also expected to leave soon: Margaret Tutwiler, who had been head of communications; Tim Carney, who had been overseeing Iraq's Ministry of Industry and Minerals; David Dunford, a senior Middle East expert; and John Limbert, the ambassador to Mauritania.

Neither Bremer nor Garner commented on that report, but Tutwiler told a reporter the plan from the beginning was for her to be in Iraq for one month, until May 15, and then return to her post as ambassador to Morocco.

Following the U.S.-issued decree on Sunday dissolving Saddam Hussein's Baath Party, Bremer was said to be considering issuing additional orders dissolving Saddam's former defense and security apparatus, including the Republican Guard and the Special Republican Guard that were loyal to him.

Myers alluded to these next steps in ridding Iraq of all vestiges of the ousted regime.

"There is absolutely no chance that Saddam Hussein and his Baathist Party or those who are following Saddam Hussein are ever going to come to power again in Iraq," Myers said. "We are deadly serious about ensuring the stability of Iraq, and the future of Iraq depends on an Iraq that is free of any hint of the former regime."

Bremer, 61, is a former assistant to former Secretaries of State William P. Rogers and Henry Kissinger. He was ambassador-at-large for counterterrorism from 1986 to 1989, and he also has served as U.S. ambassador to Holland. He most recently has been chairman of the Marsh Crisis Consulting firm.

Bremer reports directly to Defense Secretary Donald H. Rumsfeld. Gen. Tommy Franks, the Central Command chief, remains in charge of all U.S. and allied forces in Iraq and the region.

In Basra, Bremer was meeting with British officials who are responsible for establishing order in the city. Myers was meeting with British commanders and having lunch with their troops.

In some respects, including the availability of electric power, Basra is further along in recovery than is Baghdad. The power is working in most of Basra and work is under way to finish repairs of the water system.

In Qatar on Sunday, Myers said the U.S. military is pulling out of one Qatari air base and upgrading another.

The moves reflect the suddenly changed circumstances for American forces since the demise of the Saddam regime in Iraq.

Myers, who had flown overnight from Washington, told troops upon his arrival in Qatar that the American presence at an air base called Camp Snoopy would "go away" soon.

Snoopy served as a logistics hub for U.S. military operations in the Gulf region. Also, specialized Air Force planes such as the EC-130 Commando Solo airborne broadcast station flew missions over Iraq daily from Snoopy. Flight operations are to cease this month and the camp will close by mid-June.

Major changes, meanwhile, are under way at another Qatari air base used by American forces in the war. Under Pentagon ground rules for reporting on Myers' visit to Qatar that air base could not be identified in this story.

Myers said earlier that substantial improvements are in the works for that air base, including the construction of new housing.

Brig. Gen. Rick Rosborg, commander of the 379th Air Expeditionary Wing at the base, said in an interview that dozens of the approximately 140 fighter aircraft that operated from the base during the war were heading home. At the same time, additional support aircraft such as C-130s and other cargo planes are arriving in increasing numbers.