Britain's Supreme Court has taken up the case of a 29-year-old detainee held by American officials at an Afghan prison outside Bagram air base.

The two-day hearing in the case of Yunus Rahmatullah of Pakistan is one of the first times a detainee from Parwan prison - a sprawling, secretive Afghan detention complex built on the site of a former Soviet airfield - has ever made his case in a civilian court.

Unlike the U.S. prison camp at Guantanamo Bay, terror suspects at Parwan are denied access to lawyers.

Monday's hearing is in many ways academic. A lower court ordered Britain to seek Rahmatullah's release, reasoning that he was originally captured by U.K. forces in Iraq and was thus Britain's responsibility. But U.S. officials have largely shrugged off the ruling.