The UN nuclear watchdog, the International Atomic Energy Agency (IAEA), on Monday urged Iran to be granted access to the military Parchin site. \"I request Iran once again to provide access to the Parchin site without further delay, whether or not agreement has been reached on the structured approach,\" said Yukiya Amano, director-gGeneral of IAEA in a statement to the board of governors. He also expressed concern about advanced centrifuges being installed at Iran\'s Natanz nuclear plant, saying the new models were being installed for production purpose for the first time in Iran. The Parchin site has been the main concern of the agency since November 2011. Iran has previously refused to grant access to the site unless an agreement has been reached on a structured approach, a framework which would allow UN inspectors to look into Iran\'s nuclear activities.