Soltanieh suggested that the Iranian demonstration of the technical capability for such conversion, which apparently took the United States and other P5+1 governments by surprise, has rendered irrelevant the P5+1 demand to ship the entire stockpile of 20-percent enriched uranium out of the country.
"This capacity shows that we don't need fuel from other countries," said Soltanieh.
Iran began enriching uranium to 20 percent in 2010 after the United States made a virtually non-negotiable offer in 2009 to provide fuel plates for the Tehran Research Reactor in return for Iran's shipping three-fourths of its low-enriched uranium stockpile out of the country and waiting for two years for the fuel plates.
The P5+1 demand for closure of the Fordow enrichment plant was also apparently based on the premise the facility was built exclusively for 20-percent enrichment. But Iran has officially informed the IAEA that it is for both enrichment to 20 percent and enrichment to 3.5 percent.
The 1,444 centrifuges installed at Fordow between March and August -- but not connected to pipes, according to the Washington-based Institute for Science and International Security -- could be used for either 20-percent enrichment or 3.5-percent enrichment, giving Iran additional leverage in future negotiations.
Soltanieh revealed that two senior IAEA officials had accepted a key Iranian demand in the most recent negotiating session last month on a "structured agreement" on Iranian cooperation on allegations of "possible military dimensions" of its nuclear program -- only to withdraw the concession at the end of the meeting.
The issue was Iran's insistence on being given all the documents on which the IAEA bases the allegations of Iranian research related to nuclear weapons which Iran is expected to explain to the IAEA's satisfaction.
The Feb. 20 negotiating text shows that the IAEA sought to evade any requirement for sharing any such documents by qualifying the commitment with the phrase "where appropriate."
At the most recent meeting on Aug. 24, however, the IAEA negotiators, Deputy Director General for Safeguards Herman Nackaerts and Assistant Director General for Policy Rafael Grossi, agreed for the first time to a commitment to "deliver the documents related to activities claimed to have been conducted by Iran," according to Soltanieh.
At the end of the meeting, however, Nackaerts and Grossi "put this language in brackets," thus leaving it unresolved, Soltanieh said.
Former IAEA Director General Mohamed ElBaradei recalls in his 2011 memoirs that he had "constantly pressed the source of the information" on alleged Iranian nuclear weapons research -- meaning the United States -- "to allow us to share copies with Iran." He writes that he asked how he could "accuse a person without revealing the accusations against him?"
ElBaradei also says Israel gave the IAEA a whole new set of documents in late summer 2009 "purportedly showing that Iran had continued with nuclear weapons studies until at least 2007."
Soltanieh confirmed that the other unresolved issue is whether the IAEA investigation will be open-ended or not.
The Feb. 20 negotiating text showed that Iran demanded a discrete list of topics to which the IAEA inquiry would be limited and a requirement that each topic would be considered "concluded" once Iran had answered the questions and delivered the information requested.
But the IAEA insisted on being able to "return" to topics that had been "discussed earlier", according to the February negotiating text.
That position remains unchanged, according to Soltanieh. The Iranian ambassador quoted an IAEA negotiator as asking, "What if next month we receive something else -- some additional information?"