Satellite imagery of an Iranian site possibly used for work on a nuclear weapon shows crates, trucks and construction that may be linked to a renewed attempt to clean up before an inspection by the U.N.'s nuclear monitor, a nonproliferation institute said Wednesday.
The International Atomic Energy Agency - the U.N. watchdog - has repeatedly cited previous evidence of possible attempts to sanitize the Parchin site. But the report by the Institute for Science and International Security is significant because the IAEA plans to visit the site soon as part of the deal between Iran and six world powers focused on limiting Iran's nuclear programs in exchange for the removal of economic sanctions.
The institute cited commercial satellite images, saying they show "renewed activity" at the site. It said that "could be related to refurbishment or cleanup prior to any IAEA inspection or the taking of environmental samples."
It said the images show what appear to be a bulldozer or a steamroller, containers that have been repositioned and two new structures "of unknown purpose" that appeared between late May and early July.
"This renewed activity ... raises obvious concerns that Iran is conducting further sanitization efforts to defeat IAEA verification," said the Washington-based think tank, which is often consulted by the U.S. government.
In Tehran, the foreign ministry called the report "baseless (and) ridiculous," saying any construction at the site is linked to road repairs.
The photos emerged as anxiety grew on Capitol Hill over the IAEA's confidential agreement with Tehran to investigate whether the country's past atomic activity had any military dimensions. This confidential agreement is part of the nuclear accord with Iran but has not been shared with U.S. lawmakers.
Republicans have criticized the Obama administration, saying Congress has not been given access to the document outlining this agreement, which they say is needed to decide whether to vote to approve the deal.
The head of the IAEA, Director-General Yukiya Amano, met with senators on Capitol Hill on Wednesday, but said that that it was his legal obligation to keep this document confidential.
"Imagine if a country provides me with confidential information ... and I do not honor the commitment. No country will share information with us," he told reporters after the meeting.
"That is the case with the United States, too," he said. "We have a confidential agreement with the United States, and I cannot share it."
The situation is further complicated by Iran's continued refusal to allow some key military officers and scientists to be interviewed by the IAEA.
Amano said that Iran has not made Mohsen Fakhrizadeh-Mahabadi, a military officer who is suspected by the U.S. to have overseen weaponization work in Iran until at least 2003, available for debrief, the Wall Street Journal reported.
"If someone who has a different name to Fakhrizadeh can clarify our issues, that is fine with us," Amano told the Journal.