WASHINGTON, Feb 21: The United States has said that it would expect the head of the nuclear watchdog agency to seek information from Iran about a secret nuclear site when he visits Tehran.

Dr Mohammed ElBaradei, who heads the International Atomic Energy Agency, will visit Iran this week to seek more information about the country’s nuclear programme, a State Department official said on Friday.

The visit comes amid reports in the US media that Iran has renewed activity at its nuclear sites and is also building a secret centrifuge enrichment plant and other test facilities for centrifuges.

“We expect Dr ElBaradei’s visit would initiate a process of rigorous examination by the IAEA into Iran’s nuclear programme,” said a State Department spokesman Lou Fintor.

Dr ElBaradei is also conducting investigations into Iraq’s weapons of mass destruction.

On Thursday, US media quoted an Iranian opposition group, the National Council of Resistance of Iran, as saying that Iran has built a secret centrifuge enrichment plant near Isphahan and other test facilities for centrifuges in a factory near Teheran.

Also on Thursday, a Washington-based think tank reported intensive construction activities at an Iranian nuclear site. The Institute for Science and International Security also satellite pictures of the Natanz nuclear site near Kashan, showing massive construction.