Zacarias Moussaoui, a former al-Qaida operative sometimes referred to as the "20th hijacker" involved in the 9/11 attacks, claims that members of the Saudi royal family supported the terrorist organization.

In sworn testimony given last October from a Colorado federal prison where he is serving a life sentence, Moussaoui alleged that in the late 1990s he was directed by Osama bin Laden to create a digital database of al-Qaida's donors.

“Sheikh Osama wanted to keep a record who give money ... who is to be listened to or who contributed to the jihad," Moussaoui said, according to a transcript of the deposition filed in federal court in New York on Monday and published Wednesday by the New York Times.

Among them: Prince Turki Al-Faisal, then the Saudi intelligence chief; Prince Bandar bin Sultan, the longtime Saudi ambassador to the United States; and Prince Al-Waleed bin Talal, a prominent billionaire investor.

Moussaoui — a French national who was detained in Minnesota weeks before 9/11 and pleaded guilty to six terror-related charges in 2005 — also alleged that he once delivered letters from bin Laden to King Abdullah's brother, Prince Salman, and other members of the Saudi royal family. Abdullah died last month, and Salman was installed as king.

In a statement, the Saudi Arabian Embassy in Washington dismissed Moussaoui's allegations.

"There is no evidence to support Moussaoui's claim. The Sept. 11 attack has been the most intensely investigated crime in history, and the findings show no involvement by the Saudi government or Saudi officials," the statement read. "Moussaoui is a deranged criminal whose own lawyers presented evidence that he was mentally incompetent. His words have no credibility. [Moussaoui's] goal in making these statements only serves to get attention for himself and try to do what he could not do through acts of terrorism — to undermine Saudi-U.S. relations."

In 2004, the 9/11 Commission concluded there was no evidence that the Saudi government funded al-Qaida.

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"It does not appear that any government other than the Taliban financially supported al-Qaida before 9/11, although some governments may have contained al-Qaida sympathizers who turned a blind eye to al-Qaida's fund-raising activities," the commission's report said. "Saudi Arabia has long been considered the primary source of al-Qaida funding, but we have found no evidence that the Saudi government as an institution or senior Saudi officials individually funded the organization."

Moussaoui's deposition was taken as part of a motion to dismiss a civil lawsuit filed against Saudi Arabia by relatives of those killed in the Sept. 11, 2001, terrorist attacks.

During his 2006 sentencing, Moussaoui tried to fire his lawyers, who argued that he had a mental illness. But a judge ruled that he was fully competent.

And Sean P. Carter, a lawyer who participated in the October deposition, told the Times, “My impression was that he was of completely sound mind — focused and thoughtful."

In his testimony, Moussaoui also described in detail a planned truck-bomb attack on the American Embassy in London, as well as plotting attacks using crop-dusters.

Additionally, Moussaoui said that he had been directed to meet with an official in the Islamic Affairs Department of Saudi Arabia's embassy in Washington to explore "the feasibility of shooting Air Force One."

“I was supposed to go to Washington ... find a location where it may be suitable to launch a Stinger attack [on Air Force One] and then, after, be able to escape,” he said.

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