Western intelligence agencies and U.N. inspectors suspect Iran is planning to build more nuclear sites despite international demands that it open up its operations for inspection, The New York Times reported.
Comments recently made by a top Iranian official reportedly prompted inspectors to search for at least two more sites.
Ali Akbar Salehi, the head of Iran’s Atomic Energy Organization, said in an interview with the Iranian Student News Agency that President Mahmoud Ahmadinejad ordered building to begin promptly on two new plants inside mountains.
"God willing," Salehi told the News Agency, "we may start the construction of two new enrichment sites" in the Iranian new year, which began March 21.
The Times reported that U.S. officials are also suspicious of continued nuclear building by Iran and are examining satellite evidence about a number of suspected sites in the country.
They have not yet determined the sites are being used to produce nuclear fuel.
Last September, President Obama revealed the evidence of a hidden Iranian nuclear site at Qum.
On Saturday, the head of the Arab League urged the 22-nation bloc to engage Iran directly over concerns about its growing influence in the region and its disputed nuclear program.
Amr Moussa outlined his plan for closer ties with Iran, saying it would involve a forum for regional cooperation and conflict resolution that would include Iran and Turkey -- both non-Arab nations.
But the proposal could undermine U.S. and Israeli efforts to isolate Tehran amid concerns that its nuclear program aims to develop atomic weapons. It also comes as the U.S. and other Western powers push for a fresh round of sanctions over Iran's nuclear defiance. Tehran insists its program is for peaceful purposes.
I realize that some are worried about Iran but that is precisely why we need the dialogue," Moussa said.
The push to engage Tehran seems to be at least partly fueled by Arab frustration over Washington's failure to get Israel to back down on plans for more Jewish settlements on land the Palestinians want for a future state.
It also suggests that Arab nations are increasingly less likely to align with the U.S. strategy on Iran if they feel they are getting nothing in return in Mideast peace efforts.
The Associated Press contributed to this report.