Al-Iraqi, who was held by the CIA before being turned over to US military authorities, was in charge of cross-border attacks against "coalition forces", working directly with the Taliban from 2002-2004, Whitman said.
"He also in recent years was involved in plots to assassinate perceived opponents of al-Qaeda to include Pakistan President Musharraf as well as other officials."
Whitman declined to comment on when and where al-Iraqi was captured or whether US forces were directly involved in the capture.
Al-Iraqi also met al-Qaeda members in Iran, but Whitman would not say when.
A factsheet released by the Pentagon said al-Iraqi believed that al-Qaeda members in Iran "should be doing more with the fight, including supporting efforts in Iraq and causing problems within Iran".
Before September 11, 2001, he was a member of the al-Qaeda military committee that oversaw military and guerrilla operations and paramilitary training, according to the Pentagon.
He also was a member of a 10-member group of advisers to Osama bin Laden, and was known and trusted by the al-Qaeda leader and Ayman Al-Zawahiri, his deputy, the Pentagon said.
Al-Iraqi was born in the northern Iraqi city of Mosul in 1961 and served in the Iraqi military before going to Afghanistan where he spent 15 years, it said.