Iran has earmarked potential sites for 10 new nuclear enrichment plants and construction of two of them could begin this year, a nuclear energy official said on Monday.
"We have earmarked close to 20 sites and have passed the report on those to the president, however, these sites are only potential," Ali Akbar Salehi, head of the Atomic Energy Organisation, was quoted as saying on news agency ISNA.
"We should begin the construction of two enrichment sites next year ... In the two new sites, we plan to use new centrifuges."The next Iranian year begins on March 21.
Iran announced plans in November to build 10 new enrichment plants to match its existing Natanz complex. The announcement came as the United States and its allies hoped to reach an agreement for Iran to enrich uranium abroad.
Washington fears Iran's nuclear energy programme will allow Tehran to develop nuclear weapons.
Iran denies any such intention and says it only wants to generate electricity.
Analysts are sceptical whether sanctions-bound Iran, which has problems obtaining materials and components abroad, would be able to equip and operate 10 new plants.
They see Iran's claims to have plants running within a few years as a bluff in the nuclear dispute with the West.
Salehi said President Mahmoud Ahmadinejad would announce on April 9 what kind of centrifuges are to be used at the new sites.
The United States and its allies hope to get new United Nations sanctions imposed on Iran in the coming weeks over its continued enrichment work.