As the main reparations, the damaged building would be replaced with an even more spacious facility, Behrouz Kamalvandi, a spokesman for the National Atomic Energy Organization told the Islamic Republic News Agency.
David Albright of the Institute for Science and International Security similarly said the fire struck the production facility.
Israel has backed Trump's "maximum pressure" policy on Tehran aimed at forcing it to agree a new deal that puts stricter limits on its nuclear work, curbs its ballistic missile programme and ends its regional proxy wars.
When the U.S. withdrew from the nuclear deal, the work there was renewed, Kamalvandi said.
"The policy towards Iran is long-term and cross-governmental, and Iran can not be allowed to have nuclear capabilities", Ashkenazi said. Debris on the ground and a door that looked blown off its hinges suggested an explosion accompanied the blaze.
Fourth of July: Trump vows to defeat 'radical left' while virus soars
The US President also attended the 4 July American Independence Day celebrations in South Dakota. "Their goal is demolition". His comments were followed by a military flyover involving various aircraft, including B-52 bombers and F-35 fighter jets.
Iran's nuclear body has yet to provide an explanation for the cause of the incident, which came six days after an explosion near a military complex in Parchin area southeast of Tehran rocked the Iranian capital. The network said that the lab in Natanz where advanced centrifuges are assembled had been destroyed.
The deal only allows Iran to enrich uranium at Natanz facility with more than 5,000 of first-generation IR-1 centrifuges.
The site of the fire corresponds to a newly opened centrifuge production facility, said Fabian Hinz, a researcher at the James Martin Center for Nonproliferation Studies at the Middlebury Institute of International Studies in Monterey, California.
Elsewhere in his remarks, the analyst has stressed Israel's role in recent fires and explosions, asserting "the series of explosions and mysterious fires in Iran is not a coincidence" and "it will definitely intensify".
"Not every incident that happens in Iran is necessarily connected to us", Gantz told Israel Radio on Sunday morning.
Pacers guard Victor Oladipo will sit out season restart
This team has shown great resolve in responding to adversity and we fully expect this will be no different. He also has played for the Orlando Magic (2013-14 to 2015-16) and the Oklahoma City Thunder (2016-17).
Israel has said for years that it is "confident" that Iran's nuclear program is being pursued militarily with the goal of acquiring an atomic bomb.
The explosion and fire appear to have started from the inside.
"We have many open-space sheds at Shahid Ahmadi Roshan enrichment complex". It cited an "informed source" in saying the site of the incident was not related to the military.
Keivan Khosravi announced on Friday that technical and security investigation conducted by the relevant organizations has exactly discovered the cause of the accident that occurred at "Ahmadi Roshan" nuclear site in Natanz on July 2.
Tropical Storm Edouard Forming?
It is expected to encounter dry air and wind shear so it is not expected to strengthen into much more than a week tropical storm. That disturbance was a low within a larger area of low pressure off the northern Gulf Coast as of Sunday afternoon.
After the Trump administration pulled out of a nuclear agreement with Iran and other countries in May 2018 and reimposed sanctions on the Iranian economy, Tehran announced it was developing advanced centrifuges able to enrich uranium to weapons-grade levels more quickly - though global inspectors say it has stopped short of producing any such fuel.