TEHRAN - Iran announced some nuclear "achievements" on Wednesday in defiance to the western sanction threats.

In a ceremony held in Tehran, Iranian President Mahmoud Ahmadinejad unveiled nuclear fuel rods, new generation of centrifuges and a number of radioactive medicines.

In the ceremony, Ahmadinejad, symbolically, fed a home-made fuel rod made out of 20-percent enriched uranium into the core of Tehran Research Reactor.

State TV broadcast live a ceremony in which Ahmadinejad was briefed about the process of production and performance and then he fed a rod into the core of Tehran Research Reactor.

Simultaneously, the TV showed other "achievements" in Iran's nuclear technology, including the radioactive medicines for the treatment of cancer.

Ahmadinejad also unveiled a new generation of centrifuges for uranium enrichment.

In a live broadcast footage by the state TV, a model of the forth generation of domestically-made centrifuges was presented.

At the same time, a live video from Iran's central Natanz enrichment site displayed a chain of new generation of centrifuges.

Head of the Atomic Energy Organization of Iran, Fereidoon Abbasi, said in the ceremony that his country activated the first cascade of the new generation of centrifuges at its Natanz nuclear enrichment site.

Abbasi added that the move will, to a great degree, speed up the country's uranium enrichment activities and is a strong response to the Western hostilities.

Earlier on Wednesday, a report by local satellite TV from central Natanz city said the new generation of centrifuges is made of carbon fiber and performs three times as fast as the third generation.

Iran's President Mahmoud Ahmadinejad attends an unveiling ceremony of new nuclear projects in Tehran Feb 15, 2012. [Photo/Agencies]