The man, Mamduh Mahmud Salim, is believed to be the finance chief for Osama bin Laden, the Saudi dissident whom accused by the US of masterminding the two attacks.

Mr Salim faces charges in New York of conspiracy to kill US citizens and procuring weapons, including components for nuclear weapons.

He admits knowing Mr bin Laden but denies involvement in his activities.

Mr Salim was arrested in Bavaria in September. Bonn approved the extradition after receiving a pledge from the American authorities that if convicted, Mr Salim would not be sentenced to death.

Germany refuses to extradite suspects to any country where they might receive the death penalty.

Ongoing search

US federal prosecutors have been building a case against Osama bin Laden and his al Queda organisation since at least 1995.

Their efforts expanded after the embassy bombings.

Following the attacks, the US carried out military strikes against targets in Afghanistan and Sudan, which it alleged were connected with Osama bin Laden.

The strikes were denounced in the Arab and Islamic worlds and Osama bin Laden renewed his threat to wage a holy war against the US.