BAGHDAD Ñ The United States has forced the resignation of the Iraqi minister responsible for the nation's new police force.

Iraqi Interior Minister Nuri Badran resigned on Thursday amid heightened criticism of U.S.-trained security forces and police. Badran told a news conference that Coalition Provisional Authority administrator Paul Bremer was dissatisfied with the performance of both the ministry and the police.

"I am resigning now," Badran said. "Bremer is not satisfied with the performance of the Interior Ministry."

The resignation came the day after U.S. officials expressed disappointment over the performance of the police and security forces in their response to the Sunni and Shi'ite insurgency throughout Iraq, Middle East Newsline reported. U.S. officials said that in many cases Iraqi police and security personnel fled from battle or allowed Shi'ite insurgents to take over government facilities.

Officials said police and the Iraqi Civil Defense Corps exhibited almost no resistance to attacks by the Mahdi Army in such cities as Baghdad, Kut and Najaf. They said this failure left undermanned coalition forces exposed to the onslaught of the insurgents, many of them dressed in civilian clothes.

The Interior Ministry was also blamed for failing to properly screen recruits for the police and ICDC. Officials acknowledged that the ranks of Iraqi security forces have been riddled with insurgents and their supporters, many of whom later participated in ambushes of U.S. troops and private military contractors as well as the capture of government installations.

The Bush administration has announced that it will delay plans to reduce the U.S. military presence in Iraq amid the current troop rotation. Officials said the announcement reflects the lack of confidence in the capabilities of the Iraqi security forces and police.

"The Iraqi Police Service failed to warn about the attack on U.S. contractors in Falujah, and it surrendered control of its police stations and vehicles to Sadr's Mahdi Army in cities from Baghdad to Basra," Michael Knights, a defense analyst at the Washington Institute, said. "The ICDC designed by the CPA to provide paramilitary support to police and coalition forces, underperformed in its first major deployment in the Falujah fighting and failed to prevent the collapse of police forces in the face of Mahdi Army pressure in the south."

The U.S. Defense Department has appointed Maj. Gen. David Petraeus, commander of the U.S. Army's 101st Airborne Division, to head the effort to train and deploy Iraqi military and security forces. The Pentagon's decision reflected what officials termed deep dissatisfaction with the capabilities of all security agencies in Iraq.

Petraeus, who recently left Iraq after spending a year with his division, would help draft new retraining, equipping and deployment schedules, officials said. He was also meant to determine the basic needs of Iraq's military and security force so that they could ensure their missions over the next year.

Badran also attributed Bremer's decision to fire the minister to a U.S. policy of ensuring ethnic balance in the interim Iraqi Governing Council. Both Badran as well as the new defense minister, Ali Alawi, are Shi'ites.

Alawi will enter the new Defense Ministry on April 15 and will oversee the army, air force, navy, ICDC and a new Iraqi intelligence agency.

For his part, Bremer said Badran would be replaced immediately. "We anticipate filling it promptly following consultations with Iraqi leaders," the U.S. official said in a statement.