A former top aide to Osama bin Laden is scheduled to be sentenced on May 15 after his conviction in the 1998 bombings of two U.S. embassies in Africa.
The federal court in New York could send Khaled al-Fawwaz to prison for life.
The attacks in Kenya and Tanzania killed 224 people including a dozen Americans.
His lawyers say Fawwaz played a small role in the attacks and should not be given life in jail.
But prosecutors argue Fawwaz was an Al-Qaeda leader, helping spread Al-Qaeda's message of terror to the Western world.
They say he also led a terrorist training camp and a terror cell.
The Saudi Arabia-born Fawwaz was extradited from Great Britain in 2012.
Based on reporting by AP