After recent progress with Iran, it is time to tackle "more difficult" nuclear issues such as allegations of past weapons work, the head of the UN atomic watchdog told AFP in an interview.
"We started with measures that are practical and easy to implement, and then we move on to more difficult things", said Yukiya Amano, director general of the International Atomic Energy Agency.
He said "we certainly wish to include issues with 'possible military dimensions' in future steps ... We have already discussed it and will continue to discuss it at the next meeting" between the IAEA and Iran on February 8.
A November 11 agreement with the IAEA towards improved oversight over Iran's programme included six steps such as this week's visit by IAEA inspectors to the Gachin uranium mine and to a new reactor plant at Arak in December.
But the deal, separate to an accord struck with world powers on November 24 in Geneva, made no specific mention of long-standing allegations that prior to 2003, and possibly since, Iran's nuclear work had what the IAEA calls "possible military dimensions".
Two years of talks between the IAEA and Iran over these accusations, detailed in a major and controversial IAEA report in November 2011 and consistently denied by Iran as being based on faulty intelligence, went nowhere.
But Amano, 66, told AFP that Iran has not been let off the hook, saying that the November 24 accord with world powers made clear that "all past and present issues" must be resolved.