Iran said on Tuesday that it had begun loading the first of 163 fuel rods into the core of its first nuclear reactor, set to go into operation early next year, and vowed to pursue nuclear activities "in other areas."
Iran's nuclear program has spread deep concerns in the West because governments, including the United States, do not accept Tehran's insistence that it has no ambitions to build a nuclear weapon, New York Times reports.
Iran says the Russian-built Bushehr reactor will start producing nuclear energy early next year.
Despite Iran's statements about the purpose of the plant, the rest of the world remains cautious when it comes to Tehran's nuclear program.
In September, Yukiya Amano, the chief of the UN's International Atomic Energy Agency (IAEA) stated that Iran had "not provided the necessary cooperation to permit the Agency to confirm that all nuclear material in Iran is in peaceful activities."
Amano also alleged that Iran was blocking the UN agency's efforts in the country by refusing to admit certain inspectors, a charge Iran denied.
Iranian President Mahmoud Ahmadinejad has defended the country's nuclear program, calling earlier this month for American leaders to be "buried" for what he sees as threats of violence against Iran's advancements.
But President Obama remains wary of Iran's plans, reiterating that U.S. force remains an option if necessary, New York Daily News reports.