Iran will restart activities at the Arak heavy water nuclear reactor, Ali Akbar Salehi, the head of the country's Atomic Energy Organization, told lawmakers on Sunday.
The semi-official ISNA news agency cited an Iranian lawmaker, who attended Sunday's meeting.
"Iran's enemies know that we have the knowledge and capability to produce nuclear energy, but we don't want to produce nuclear weapons," Salehi was quoted as saying.
Heavy water can be employed in reactors to produce plutonium, a fuel used in nuclear warheads.
Tension has been running high between Iran and the West since U.S. President Donald Trump unilaterally withdrew his country from a 2015 nuclear deal and imposed sanctions on Iran.
In response, Tehran last month announced measures to scale back its commitments to the deal, citing lack of action from the Europeans to save the agreement.
By Khalaf Rasha in Tehran