"It's in the process," he told The Associated Press in Davos, where he was attending the World Economic Forum (search).
Asked when the trials would begin, he replied: "That's not in my hands." He said the identities of those to be tried "has not been announced."
The United States said the Iranian plan was not acceptable to Washington.
"We've heard these reports before. It's not new. Our position hasn't changed. We have long made it clear that we believe that Iran should turn over all suspected Al Qaeda operatives to the United States or to countries of origin or third countries for further interrogation and trial," said State Department deputy spokesman J. Adam Ereli.
Intelligence Minister Ali Yunesi confirmed for the first time in July that Iran was holding "a large number of small and big-time elements of Al Qaeda" who had illegally crossed the border.
In September, Iran gave the U.N. Security Council (search) the names of 225 suspected Al Qaeda operatives it detained and returned to their home countries.
U.S. officials have said intelligence suggests that Al Qaeda figures in Iran include Saif al-Adl, a top Al Qaeda agent possibly connected to May bombings in Riyadh, Saudi Arabia; Abu Mohammed al-Masri, wanted in connection with the bombings of two U.S. embassies in East Africa in 1998; Abu Musab Zarqawi, whom some U.S. officials describe as the key link between Al Qaeda and toppled Iraqi leader Saddam Hussein; and Al Qaeda head and mastermind Usama bin Laden's eldest son, Saad.
The Al Qaeda operatives are believed to have fled to Iran from neighboring Afghanistan during the Taliban's (search) fall in late 2001 or early 2002.