Osama Bin Laden evaded a US-led offensive in Afghanistan in 2001

The man, named as Muhammad Rahim, helped arrange Bin Laden's escape from his Tora Bora hideout in Afghanistan in 2001, US officials say.

He was transferred to the Pentagon from CIA custody earlier this week, a Pentagon spokesman said.

The CIA captured Rahim, said to be an Afghan national, in the summer of 2007.

A statement from CIA director Michael Hayden to intelligence staff said Rahim was "a tough, seasoned jihadist", whose arrest was a blow to more than one terror network.

"His combat experience, which dates back to the 1980s, includes plots against US and Afghan targets," Mr Hayden said.

"Rahim is perhaps best known in counter-terror circles as a personal facilitator and translator for Osama Bin Laden and other al-Qaeda leaders."

'Most trusted'

Pentagon spokesman Bryan Whitman said Rahim was a close associate of Bin Laden and had ties to al-Qaeda groups throughout the Middle East.

Osama Bin Laden remains top of Washington's 'Most Wanted' list

"He is one of [Osama Bin Laden's] most trusted facilitators and procurement specialists," Mr Whitman said.

"He helped prepare Tora Bora as a hideout for Osama Bin Laden. He assisted al-Qaeda's exodus from the area in late 2001."

Rahim will be given access to the International Committee of the Red Cross at the Guantanamo Bay camp in Cuba, and will be treated in accordance with US and international law, Mr Whitman added.

CIA officials say the transfer to the Pentagon is the first such to take place for about a year.

US forces are believed to have come closest to trapping Bin Laden in a complex of caves in the mountainous Tora Bora region near the Pakistani border.

The hunt for him began following the 11 September 2001 terror attacks on the US by al-Qaeda operatives.