Iran said operations had begun at a new uranium milling production plant and two extraction mines on Tuesday.
The news comes days after talks between Iran and six world powers in Kazakhstan over Iran's much-disputed nuclear program failed to produce results.
"The Islamic Republic of Iran has unveiled three nuclear achievements in the country’s central province of Yazd on the occasion of the National Day of Nuclear Technology," Iranian state news, Press TV said.
Saghand mines 1 and 2 in Yazd province will extract uranium to produce about 60 tons yellowcake annually at the Shahid Rezaeinejad plant in Ardakan. But as Reuters points out, some analysts believe Iran has a limited supply of raw uranium.
Yellowcake can be processed into enriched uranium to fuel nuclear power plants, and if highly enriched it can also be used as nuclear weapons material.
Western powers claim Iran is pursuing nuclear weapons technology that would allow it to build an atomic bomb, while Iran says it's building a civilian program for energy and medical purposes, a right under the Nuclear Nonproliferation Treaty.
On Monday, the Islamic Republic rejected an offer by the five permanent UN Security Council members and Germany to stop its nuclear work in exchange for a modest easing of sanctions that have damaged Iran's economy.
Western nations have "tried their utmost to prevent Iran from going nuclear," President Mahmoud Ahmadinejad said in a speech to Iran's Atomic Energy Organization on Tuesday. "But Iran has gone nuclear."
"This nuclear technology and power and science has been institutionalized," President Ahmadinejad added. "All the stages are in our control and every day that we go forward a new horizon opens up before the Iranian nation."