Saifullah Paracha, 57, who was arrested 19 months ago and is now being held in Guantanamo Bay, Cuba, told the al Qaeda operatives that he knew where to get nuclear weapons, according to documents field with the US District Court in Washington.
The papers filed in the court identify Paracha as a participant in a plot to smuggle explosives into the United States and to help al Qaeda hide large amounts of money.
A media report quoted Paracha as vigorously denying to a review tribunal in November at the US Naval base in Cuba any ties with al-Qaeda.
"Is a nuclear weapon something I could buy off the shelf? Can you buy it from Tony Blair?" he was quoted to have said referring to the British Prime Minister.
His son Uzair, 25, was also arrested in New York in 2003 on the charges of trying to help an al Qaeda operative get into the United States and his trial is set for March 21.
Paracha operates a TV production company along with International Merchandise, which imports clothing in New York. Investigators charged that father and son met with top al-Qaida leaders in Pakistan.
Three months after his son's arrest, Paracha took a commercial flight from Pakistan to Thailand in July 2003 to meet with Kmart buyers. He was turned over to US forces, who took him to Bagram air base in Afghanistan, where he was interrogated for more than a year, then shipped to Guantanamo last September.
The Pakistani Daily Dawn quoted his wife, Farhat Paracha, as saying that although her husband had met Osama bin Laden twice, he had nothing to do with terrorism.
The paper also quoted Pakistani Ambassador in Washington Jehangir Karamat as saying that there was no evidence that Pakistani scientists had sold nuclear technology to al Qaeda or any other militant group.
More from rediff