Arabic television al Jazeera has shown what it says is a new videotape of al Qaeda leaders Osama bin Laden and Ayman al-Zawahri walking in mountains.
In an audio tape run with the pictures, a man said to be Bin Laden praised the September 11 attackers.
The airing of the tape came on the eve of the second anniversary of the September 11 attacks in New York and Washington, which were widely blamed on al Qaeda.
"Whoever wants to be taught about loyalty and honesty should have known them (the attackers)...They were the most honest and the bravest," the voice said.