US Defence Secretary Donald Rumsfeld has said the revelations about the abuse of Iraqi prisoners by American soldiers were "a body blow".
Mr Rumsfeld visited the Baghdad prison during a surprise trip to Iraq
He made the comment during a visit to the Abu Ghraib prison in Baghdad, where the cases of abuse were photographed.
Mr Rumsfeld told troops at the jail and at coalition headquarters that those involved would be brought to justice.
The embattled defence secretary - who was on a surprise trip to Iraq - told US soldiers that he was "a survivor".
Mr Rumsfeld, travelling under tight security, landed at Baghdad airport and later held meetings with senior US military officers in the capital.
He met Lieutenant General Ricardo Sanchez, the US commander in Iraq, and Major General Geoffrey Miller, the new head of US prisons in the country.
After speaking to soldiers at Abu Ghraib jail, Mr Rumsfeld addressed US troops at coalition headquarters in Baghdad, telling them the photographs of abuse had "soiled America's reputation".
He insisted that the pictures were not representative of American values, and that both he and President Bush had faith in the troops serving in Iraq.
Referring to media coverage of the war, the defence secretary said he had "stopped reading the newspapers".
"It's a fact. I'm a survivor," he said.
As Mr Rumsfeld flew in for his seven-hour visit, US troops were engaged in fresh clashes with fighters loyal to radical cleric Moqtada Sadr in Karbala.
New abuse pictures
On Wednesday, members of the US Congress expressed anger and disgust after seeing new pictures of Iraqi prisoners being abused by American soldiers.
They are said to have included images of Iraqi detainees cowering before snarling military dogs and men forced into sexual acts.
Mr Rumsfeld told reporters that, while he was willing for all such pictures to be released, lawyers were advising against it on the grounds that such images could be construed as degrading to the prisoners - and thus be in violation of the Geneva Conventions.
"At the present moment, I don't know anyone in the legal shops in any element of the government that is recommending that," he said.
But on the 15-hour flight from the US, Mr Rumsfeld told reporters he was not in Iraq to cover up the scandal.
Mr Rumsfeld flew in with military chief Richard Myers
"If anybody thinks that I'm [in Iraq] to throw water on a
fire, they're wrong," Reuters news agency quoted him as saying.
"We care about the detainees being treated right. We care about soldiers behaving right. We are about command systems working," he added.
On Wednesday, Mr Rumsfeld defended interrogation techniques used by the military in Iraq.
He told a Senate committee that methods such as sleep deprivation, dietary changes and making prisoners assume stress positions had been approved by Pentagon lawyers.
Meanwhile, it has emerged that the International Committee of the Red Cross (ICRC) has issued a new report criticising the imprisonment of suspects at Guantanamo Bay, Cuba.
Fourth trip since war
A senior Pentagon official told reporters travelling with Mr Rumsfeld that the ICRC had delivered the "critical" report to the US State Department this week.
The Red Cross has repeatedly complained about the imprisonment at the US naval base of more than 500 people, most of them captured in Afghanistan and held without charge.
It is Mr Rumsfeld's fourth visit to Iraq since the fall of Saddam Hussein.
Also travelling with the US defence secretary was General Richard Myers, chairman of the Pentagon's Joint Chiefs of Staff.