The Bush administration said Friday it shares the concern of the United Nations' top human rights official about abuses of Iraqi detainees by U.S. soldiers, but it is downplaying a suggestion the behavior might amount to war crimes and says the U.S. military justice system is competent to handle such cases.

The State Department says the United States is taking "very seriously" the criticisms on Iraq leveled by the acting U.N. High Commissioner for Human Rights Bertrand Ramcharan, but is also making clear its view that abuses can, and should be, dealt with by the U.S. military and not by an international war crimes body.

The 45-page report by Mr. Ramcharan in Geneva says U.S.-led forces in Iraq had committed "serious" violations of international humanitarian law and had mistreated ordinary Iraqis.

The U.N. official said coalition troops had been able to act with impunity against detainees and urged the appointment of an international jurist to monitor their behavior. He said the willful killing, torture or inhumane treatment of detainees might be designated as war crimes by a competent tribunal.

A news briefing, State Department spokesman Adam Ereli said the United States had cooperated with Mr. Ramcharan in the preparation of the report and is already moving aggressively to investigate and punish those responsible for the highly publicized abuses at Baghdad's Abu Ghraib prison.

?The question of investigation, prosecution and judgment is something that we are already doing ourselves,? he said. ?And that more importantly, or equally important, is that it is something we are doing openly, transparently and in fact quite publicly, so that the whole world will know that we hold ourselves accountable to the same standards that we ask others to follow.?

Mr. Ereli said suggestions in the U.N. report of a broader pattern of abuse by U.S. led forces are troubling and that the United States had asked Mr. Rancharan's office for more details on individual cases cited.

On the idea of an international forum for prosecution, Mr. Ereli said the U.S. military justice system is "competent to act" on any abuses that occurred.

The spokesman said the U.N. report is not entirely critical and acknowledged that U.S.-led military action had removed a government that had committed "shocking, systematic and criminal" human rights violations and may have put Iraq "on the road" to democratic governance.