Holder stressed he was launching a preliminary inquiry, but the decision still seemed to put him at odds with the White House.

'I fully realise that my decision to commence this preliminary review will be controversial,' Holder said in a statement. 'Given all of the information currently available, it is clear to me that this review is the only responsible course of action for me to take.'

The repeated allegations have reportedly severely harmed morale at the CIA. Its current director, Leon Panetta, suggested he was opposed to reopening cases that had been closed by the Justice Department years earlier.

'My primary interest ... is to stand up for those officers who did what their country asked and who followed the legal guidance they were given,' Panetta wrote in the letter, which was posted on the news website Politico.

The new inquiry was welcomed by human-rights groups, but many said it should be expanded to include Bush administration officials. Legal memos that supported practices including water-boarding, a technique that simulates drowning, were released earlier this year.

The CIA inspector general's report provides compelling official confirmation that the CIA committed serious crimes, said Joanne Mariner of Human Rights Watch. A full criminal investigation into these crimes, and who authorised them, is absolutely necessary.

The White House earlier Monday said it created a new interrogation team that will be based at the FBI, the chief domestic law-enforcement agency. It will be overseen by the National Security Council, which reports directly to the president.

The change moves responsibility for interrogating high-value suspects away from the CIA. It was recommended by a Justice Department taskforce whose findings were released Monday.

The White House has said that any final decision on whether to prosecute CIA officers for prisoner abuse will be left to Holder.

'The president has said repeatedly that he wants to look forward, not back,' White House spokesman Robert Gibbs said in a statement. 'Ultimately, determinations about whether someone broke the law are made independently by the attorney general.'

Monday's decisions are part of an ongoing review of policies to handle terrorist suspects captured both on military battlefields, such as Afghanistan, and around the world.

Obama has already directed the closure of the controversial detention facility in Guantanamo Bay, Cuba, by the end of the year.