Osama bin Laden's son-in-law, Suleiman Abu Ghaith, unexpectedly testified on Wednesday at his trial on terrorism-related charges and denied that he had any role in al-Qaeda plots against the U.S.

Abu Ghaith, 48, is one of the highest profile people with purported links to al-Qaeda to be tried in a U.S. civilian court. Prosecutors in federal court in New York have accused him of serving as a spokesman and recruiter for al-Qaeda and of knowing about planned attacks against Americans.

Under questioning from his lawyer, Stanley Cohen, Abu Ghaith described meeting Osama bin Laden, a founder of al Qaeda, in Afghanistan just hours after the hijacked plane attacks of Sept. 11, 2001, which killed nearly 3,000 people.

Mountain meetings

After driving several hours into the mountains, Abu Ghaith said that he met bin Laden and several of his lieutenants, including Ayman al-Zawahiri, the Egyptian now considered al-Qaeda's leader, inside a cave. Bin Laden was killed in May 2011 by U.S. forces at his hideout in Pakistan.

Abu Ghaith testified that bin Laden asked him if he had heard about the attacks. Abu Ghaith said he first learned about the attacks from news reports.

"We are the ones who did it," bin Laden said, according to Abu Ghaith. "What do you expect to happen?"

Abu Ghaith, who was speaking through an interpreter, said he predicted that the United States would not rest until it had accomplished two things: killing bin Laden, and toppling the Taliban government in Afghanistan.

"He said, 'You are being too pessimistic,'" Abu Ghaith told jurors.

He acknowledged making several videos at bin Laden's request, including one in which he warned that a "storm of airplanes" was coming, but denied that he had any advance knowledge of other plots, such as the shoe bomb that Briton Richard Reid attempted to detonate aboard an airplane in 2002.

Instead, he said, bin Laden asked him to deliver a "message to the world" in his role as a speaker and an imam. His speeches were based on talking points that bin Laden gave him, he said.

He also claimed that some videos were an attempt to counter the propaganda against Muslims from the U.S.

"My intention was not to recruit anyone," he said. "My intention was to deliver a message, a message I believed in, that oppression, if it befalls any nation, any people, any category of people, that category must revolt. What happened was a natural result of the oppression that befell Muslims."

Abu Ghaith also said he never became a member of al-Qaeda.

A teacher and imam in Kuwait, Abu Ghaith said he travelled to Afghanistan for the first time in June 2001 to learn about the newly installed Taliban.

While there, he received a message from bin Laden asking for a meeting. Despite knowing that bin Laden was suspected of planning the attacks on two U.S. embassies in Africa in 1998 and the suicide bombing of the U.S.S. Cole in 2000, he said he agreed.

"I wanted to see what he had, what it is that he wanted," he said.

"Did you ever discuss terrorist attacks?" Cohen asked.

"No," Abu Ghaith said. "Not at all."

Al-Qaeda training camps

Abu Ghaith said that before Sept. 11, 2001 his contribution to bin Laden's organization consisted of giving religious speeches to fighters at training camps in Afghanistan.

Bin Laden, he said, told him that the camps were a "hard life," full of "weapons, training, roughness." He asked him to speak to the men to give them "merciful hearts."

Abu Ghaith's decision to testify came a day after U.S. District Judge Lewis Kaplan ruled that jurors would not hear testimony from Khalid Sheikh Mohammed, the accused mastermind of the Sept. 11 attacks. Mohammed is being held at the U.S. military prison in Guantanamo Bay, Cuba.

Abu Ghaith said on Wednesday that he met Mohammed while in Afghanistan but that they did not discuss any planned attacks.