Iranian President Mahmoud Ahmadinejad unveiled on Wednesday a new generation of centrifuges for uranium enrichment.
In a live broadcast by state TV, a model of the fourth generation of domestically-made centrifuge was presented.
The 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 on Wednesday.
Abbasi added that the move will, to a great degree, speed up the country's uranium enrichment activities and is a strong response to Western hostilities.
Earlier on Wednesday, a report by the local satellite TV from Natanz city said the new generation of the centrifuge is made of carbon fiber and performs three times as efficiently as the third generation.
Ahmadinejad also said 3,000 more centrifuges had been added to his country's uranium enrichment effort.
The developments underlined Teheran's determination to forge ahead with its nuclear activities despite increasingly tough sanctions from the West - and speculation that Israel or the United States could be months from launching military strikes against it.
Iran portrayed the advances as evidence it was only interested in peaceful nuclear goals, under the slogan "nuclear energy for all, nuclear weapons for none".
Russian Foreign Minister Sergei Lavrov on Wednesday urged Teheran to cooperate with the world's nuclear energy watchdog to resume stalled talks.
"We would like to encourage the Iranians to work with the agency, we encourage strongly for them to continue dialogue on specific suspicions," Lavrov said at a news conference in The Hague on a two-day visit to the Netherlands.
Lavrov's visit to the Netherlands comes as tensions rose between the West and Iran over Teheran's nuclear activities, which the United States and its allies fear masks a drive for atomic weapons.