Obama signed off the unit, named the High-Value Detainee Interrogation Group (HIG) late last week, the Washington Post reported citing senior administration officials.

Made up of experts from several intelligence and law enforcement agencies, the interrogation unit will be housed at the FBI but will be overseen by the National Security Council -- shifting the centre of gravity away from the CIA and giving the White House a direct oversight.

Seeking to signal a clean break from the Bush administration, Obama moved to overhaul interrogation and detention guidelines soon after taking office, including the creation of a task force on interrogation and transfer policies, the Post noted.

The task force recommended the new interrogation unit, along with other changes regarding the way prisoners are transferred overseas, the report said.

A separate task force on detainees, which will determine the fate of prisoners at Guantanamo Bay, Cuba, and future regulations about the duration and location of detentions of suspected terrorists, has not concluded its work.

Under the new guidelines, interrogators must stay within the parameters of the Army Field Manual when questioning suspects.

Officials said the task force concluded that "the Army Field Manual provides appropriate guidance on interrogation for military interrogators and that no additional or different guidance was necessary for other agencies."

Using the Army Field Manual means certain techniques in the grey zone between torture and legal questioning -- such as playing loud music or depriving prisoners of sleep -- will not be allowed. Which tactics are acceptable was an issue "looked at thoroughly," one senior official said.

Obama had already banned certain severe measures that the Bush administration had permitted, such as waterboarding.

The task force advised that the group develop a "scientific research programme for interrogation" to develop new techniques and study existing ones to see whether they work. The unit would determine a set of best practices on interrogation and share them with other agencies that question suspects.