At the ceremony in Tehran today, Ahmadinejad called for a world free of nuclear weapons and said confrontations could be avoided if real justice was implemented throughout the world.
"As the servant of the people, I feel bound to protect and preserve the independence and the national interests of the country and the culture and the rules of Islam," Ahmadinejad said. "[It's also my duty] to defend the rights of Iranian citizen's inside and outside the country."
The 48-year-old conservative former mayor of Tehran won a landslide victory in June. His election means all the main institutions of Iran's political system will be in the hands of conservatives.
Ahmadinejad says he will form a government that will "follow the pure Islamic culture."
Ahmadinejad comes to office with Iran in the midst of a row with the West over its nuclear program. Iran has said it is restarting some nuclear activities because the European Union was too slow to offer incentives for Tehran to end its nuclear-fuel work.
Iran has denied U.S. accusations that its nuclear-energy program is a screen for a nuclear-weapons program.
(compiled from agency reports)
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