Vienna: An image said to come from inside an Iranian military site shows an explosives containment chamber of the type needed for nuclear arms-related tests that UN inspectors suspect Tehran has conducted at the site.
Iran denies such testing and has neither confirmed nor denied the existence of such a chamber.
The image was provided to a news agency by an official of a country tracking Iran`s nuclear programme who said the drawing proves the structure exists, despite Tehran`s refusal to acknowledge it.
The official said he could not discuss the drawing`s origins beyond that it was based on information from a person who had seen the chamber at the Parchin military site, adding that going into detail would endanger the life of that informant.
His country, a member of the International Atomic Energy Agency, is severely critical of Iran`s assertions that its nuclear activities are peaceful and asserts they are a springboard for making atomic arms.
A former senior IAEA official said he believes the drawing is accurate.
Olli Heinonen, until last year the UN nuclear agency`s deputy director general in charge of the Iran file, said it was "very similar" to a photo he recently saw that he believes to be the pressure chamber the IAEA suspects is at Parchin.
He said even the colours of the drawing matched that of the photo.
After months of being rebuffed, IAEA and Iranian officials meet starting tomorrow in Vienna, and the IAEA will renew its attempt to gain access to the chamber, allegedly hidden in a building. Any evidence that Iran is hiding such an explosives containment tank, and details on how it functions, is significant for IAEA investigations.
Beyond IAEA hopes of progress, that two-day meeting is being closely watched by six powers trying to persuade Iran to make nuclear concessions aimed at reducing fears that it may want to develop atomic arms as a mood-setter for May 23 talks between the six and Tehran in Baghdad.
Warnings by Israel that it may attack Iran`s nuclear facilities eased after Iran and the six -- the United States, Russia, China, Britain, France and Germany -- met last month and agreed there was enough common will for the Baghdad round.
But with the Jewish state saying it is determined to stop Iran before it develops the capacity to build nuclear weapons, failure at the Iraq talks could turn such threats into reality.
The IAEA has been stonewalled by Iran for more than four years in attempts to probe what it says is intelligence from member states strongly suggesting that Iran secretly worked on developing nuclear weapons.