The project is aimed at developing the first phase of Bushehr Nuclear Power Plant which is scheduled to be implemented in the next eight years, said Ali Akbar Salehi, head of the Atomic Energy Organization of Iran, at the ceremony in Bushehr.
The nuclear energy development is essential for Iran as it is a "secure and sustainable" energy resource for the next generation, said Salehi.
It is also a "source of strength and might" for the country, he added.
That's why the enemies are seeking to deprive Tehran of this source of power, the Iranian official noted.
Iran aims to generate more than 3,000 megawatts of nuclear energy in 2027, which will enable Iran to cut over 21 million tons of polluting gases annually.
Salehi said earlier that the extension of the Bushehr plant will increase the share of nuclear power in Iran's electricity supply well beyond the current 2.7 percent.
The first 1,000-megawatt unit of the Bushehr Nuclear Power Plant was completed by Russia in May 2011.
Iran and Russia later agreed to continue to develop the Bushehr plant. According to the agreement, the second phase would consist of two units with a cumulative output capacity of 2,114 megawatts.