Iranian President Mahmoud Ahmadinejad announced some nuclear "achievements" on Wednesday in a ceremony held in Tehran.
Ahmadinejad unveiled nuclear fuel rods, new generation of centrifuges and a number of radioactive medicines in defiance to the western sanction threats.
He was briefed about the process of production and performance and then he fed a home-made fuel rod made out of 20-percent enriched uranium into the core of Tehran Research Reactor, Xinhua reported.
The Iranian State TV broadcast 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.
Abbasi also said that Iran will start producing new yellow cake next Iranian year beginning on March 20, 2012.
Abbasi, head of Iranian nuclear industry, said that the achievements of the Islamic republic in the nuclear field is outstanding since the western countries did not believe that Iran will make such a progress despite sanctions.
President Ahmadinejad said in the ceremony that Iran has added 3,000 new centrifuges to its uranium enrichment cycle and the number of active centrifuges in the country stands at 9,000.
Ahmadinejad said that Iran is ready to share its nuclear know- how with other members of the International Atomic Energy Agency (IAEA).
He also called on the country's security officials to protect its nuclear scientists.
The president asked the Iranian Atomic Energy Organization officials to build 4 more nuclear research reactors in 4 corners of the country for further research work and producing the radio medicines.
He said that when, two years ago, Iran told western countries that if Iran is not provided with the fuel rods for its research reactor, the country will produce its own, the western countries did not believe that, now, the Iranian nation proved that they can.
The Arabic language Al-Alam state TV reported on Wednesday that Iran has replied to the EU's letter on the resumption of the nuclear talks with the G5+1.
The G5+1 comprises permanent UN Security Council members Britain, China, France, Russia and the United States, plus non- permanent member Germany.
Al-Alam did not provide details on the time of the response or any suggestions for the time and venue of the talks.
Iran's chief nuclear negotiator, Saeed Jalili, announced the Islamic republic's readiness for the resumption of nuclear talks with the world's major powers in a response to a letter from the EU foreign policy chief Catherine Ashton, the official IRNA news agency reported on Wednesday.
"The success of the (next round of nuclear) talks is subject to the constructive response of the G5+1 to the initiatives of the Islamic republic," the letter was quoted as saying.
The European Union (EU) said Wednesday that it has received a letter from Iran offering to restart the nuclear talks.
"We received the letter today and we're studying it, we're consulting with our partners," Maja Kocijancic, spokeswoman of EU foreign policy chief Catherine Ashton told Xinhua over telephone.
She declined to make more comments, saying that she could only talk so much on the issue for the time being.
The EU last month decided to impose additional sanctions on Iran, focusing on its central bank and oil exports.
Up to now, some 400 Iranian assets in the continent have been frozen and 113 people subjected to visa ban and asset freeze.