Iranian President Hasan Rouhani, right, met Yukiya Amano, left, Director General of the International Atomic Energy Agency at the weekend ahead of a deadline for Tehran to answer allegations of past nuclear weapons research. Agence France-Presse/Getty Images The chief of the International Atomic Energy Agency said a weekend visit to Tehran was “useful” as the IAEA continues to push for clarification on Iran’s previous nuclear work. Iran is scheduled to deliver information on two key aspects of its past nuclear work by next Monday. The West suspects the research was aimed at developing nuclear weapons , which Tehran denies. The intensifying talks between Iran and the IAEA are separate from the broader international talks over Iran’s nuclear future, but are considered critical to the success of those talks. The visit to Iran by Yukiya Amano, IAEA’s director general, was his first since a broad agreement last November in which […]