A new American administrator has arrived in Iraq in a shake up of the U.S. leadership team there. The veteran diplomat, Paul Bremer, is taking charge of the political and physical reconstruction of Iraq following the ouster of Saddam Hussein by the U.S.-led invasion.

Mr. Bremer arrived in the southern Iraqi city of Basra, accompanied by the man he will replace, retired General Jay Garner. Along with them was the chairman of the U.S. joint chiefs of staff, General Richard Myers.

Mr. Bremer said he looks forward to what he called a wonderful challenge, helping Iraq recover from what he described as a despotic regime.

Mr. Bremer arrived in Iraq as part of an overhaul of the United States' post-war leadership team. The chief administrator for Baghdad, Barbara Bodine, has been recalled to the State Department three weeks after she arrived in Iraq.

And Mr. Garner is expected to leave Iraq in the coming weeks, once Mr. Bremer settles into his new position.

Many Iraqis complain that a month after the fall of Saddam Hussein, the Americans have not acted quickly enough to restore security and basic services.

Carjackings and robberies are common. Looters and arsonists still roam Baghdad. Electricity is sporadic. Telephones are dead. Gasoline is scarce. And garbage is not collected.

Money is also tight because banks and most businesses have remained closed and many workers have not been paid since March.

Another big challenge facing Mr. Bremer is the task of helping Iraq establish an interim government. He will work with representatives of Iraq's various political, ethnic and religious factions who are planning a national convention in June to select their new leaders.