The announcement came as US Defence Secretary Donald Rumsfeld requested that autopsies be conducted when detainees die, officials said on Thursday.
Rumsfeld wrote in a memo released by the Pentagon that he must be notified personally of the death of an enemy prisoner of war, civilian internee or anyone else in military custody.
In a move apparently aimed at preserving evidence, he also directed that remains not be washed before being placed in a clean body bag, and that any objects with the body other than weapons or ammunition be "left undisturbed."
Sanchez requests removal
Lieutenant General Ricardo Sanchez, who commands US-led forces in Iraq, asked to be removed as the officer who reviews the ongoing investigation by Major General George Fay in order to allow his own conduct to be scrutinised, defence officials said.
"It's Sanchez saying, 'I want to be investigated. I want to make sure that I'm not missed'"
Lawrence Di Rita,
chief Pentagon spokesman
The Fay investigation was one of several launched by the Pentagon in the wake of the physical and sexual abuse of Iraqi prisoners at the Abu Ghraib jail outside Baghdad.
The new measures were announced as President George Bush told reporters in Savannah, Georgia, at the end of the G8 summit that he had only authorised lawful questioning methods for prisoners.
"What I have authorised is that we stay within US law," Bush said when asked what measures of interrogation he would authorise if the US had a terror suspect in custody it knew was planning an attack.
"I'm going to say it one more time. In fact, maybe I can be more clear. The instructions went out to our people to adhere to law," he said.
"That ought to comfort you. We're a nation of law. We adhere to laws. We have laws on the books. You might look at those laws, and that might provide comfort for you. And those
were the instructions from me to the government."
Donald Rumsfeld wants to be
notified of any detainee deaths
In Washington, Lawrence Di Rita, chief Pentagon spokesman, said a four-star officer likely would be named to join the investigation, which had been expected to be completed in June, but will now be delayed.
Di Rita said Fay was "absolutely not" being sacked, but the probe was being "augmented" to allow a more senior officer to "pick up those portions of the Fay investigation that would
involve Sanchez and his staff activities."
"It's Sanchez saying, 'I want to be investigated. I want to make sure that I'm not missed,'" Di Rita said, stopping short of saying Sanchez wanted to clear his own name.
"To clear his own name suggests that he's concerned his name needs to be cleared."
'Sanchez was careful'
Di Rita said that "it appears that Sanchez followed this thing carefully and did all the right things."
Fay, Army deputy chief of staff for intelligence, opened an investigation in April of interrogation practices by intelligence officers at US-run prisons in Iraq.
"I'm going to say it one more time. In fact, maybe I can be more clear. The instructions went out to our people to adhere to law"
Sanchez last year ordered military intelligence to take control of Abu Ghraib, but has denied knowledge of the abuse before the chain of command was notified in January.
The Army said last month it was investigating the deaths of 32 prisoners in Iraq and another five in Afghanistan since August 2002. A number of the deaths were deemed to be homicides, but autopsies were performed in only 23 cases.
The new rules require the commander of a military unit with custody of a prisoner to immediately report any death to the investigative agencies of the service involved, which will then inform the Office of the Armed Forces Medical Examiner, which conducts autopsies and will be responsible for finding the cause of death.
Under past practice, some prisoner deaths were never reported to the medical examiner's office.