Iran's quest for fully-fledged nuclear status passed an important landmark on August 21 when Russia began loading fuel into a power plant delayed for more than three decades.
The $1 billion Bushehr facility was ushered into being amid a blaze of fanfare by Iranian officials hailing it as a triumph over Western hostility to the country's nuclear aspirations.
The plant, at a spot 12 kilometers outside Bushehr on the Persian Gulf, has been built by Russian technicians and will be powered by fuel shipped in from Russia.
The inaugural ceremony was attended by Iranian and Russian nuclear officials, including the head of the Iranian Atomic Energy Organization, Ali Akbar Salehi, and Sergei Kiriyenko, the head of Russia's Rosatom nuclear agency.
Salehi said Iran was grateful to Russia for its help with launching the country's first nuclear power plant.
"[Russia] has cooperated with the Iranian nation. They have secured a place in the history of the Islamic Republic of Iran, and made their name known. They have facilitated the launch of the nuclear energy at this power plant, and this has happened in the hands of our friend and neighbor Russia," Salehi said.
A defiant Salehi later told a news conference, "Despite all pressures, sanctions, and hardships imposed by Western nations, we are witnessing the start-up of the largest symbol of Iran's peaceful nuclear activities."
Kiriyenko said the construction of the nuclear plant was a "clear example" showing that any country that cooperates openly with the International Atomic Energy Agency (IAEA), the United Nations nuclear watchdog, has the right to peaceful nuclear technology.
The inauguration marked the end of a long saga first begun in 1974 when French and German scientists began constructing two reactors at the site under commission from Iran's Western-backed monarchy.
The reactors were only partially complete at the time of the 1979 Islamic Revolution that toppled the last shah, Mohammad Reza Pahlavi, and the project was subsequently halted. During the 1980-88 Iran-Iraq War, the site was badly damaged and the equipment looted.
The scheme was revived in the 1990s with Russian help but has run into repeated difficulties amid claims by Russia that Iran was delaying payments.
Now Iran says the new facility will be the first in a network of nuclear power plants it promises will provide 20,000 megawatts of electricity by 2020 and enable it to export more oil and natural gas.
The plant comes online at a time when international concerns about Iran's nuclear activities are at a peak over fears that the country's leadership is seeking atomic weapons capability. Iranian officials deny that and insist the country's nuclear program is for peaceful purposes.
Iran has already faced four separate rounds of United Nations Security Council sanctions, as well as separate U.S. and European Union embargoes, over its refusal to halt uranium-enrichment work being carried out in at least two other facilities, Natanz and Fordow, near Qom.
Despite that, the Bushehr plant is relatively uncontroversial compared to the uranium-enrichment facilities.
The U.S. State Department has said it does not regard the facility as a potential proliferation risk because Russia has committed itself to taking back the reactor's spent fuel and processing it themselves. Spent nuclear fuels rods will be returned to Russia to assuage U.S. concerns that Iran might be able to reprocess the material into weapons-grade plutonium -- a different route to building a bomb from highly enriched uranium.
The reactor, which will have an operating capacity of 1,000 megawatts, is also subject to strict monitoring by the IAEA.
Richard Dalton, a former British ambassador to Tehran, says the Bushehr reactor is gaining broad international acceptance because it is a "legitimate activity."
"It is all taking place under IAEA safeguards. There is also the factor that it's been a long time coming. This is project that is 35 years old and has been accepted by nearly all countries for nearly all that period of time as legitimate under the Nonproliferation Treaty as it's a civil power project," Dalton says.
"The country which particularly opposed it and held out against it, the United States, has come round in the last few years to realizing that, whereas it might be undesirable from their point of view, it's not something that they could stop."
Not everyone has been reassured. Last week, John Bolton, the hawkish former U.S. ambassador to the United Nations, raised the specter of an Israeli military strike on the reactor -- a prospect widely deemed to be highly unlikely.
"What this does is give Iran a second route to nuclear weapons in addition to enriched uranium. It's a very huge, huge victory for Iran," Bolton, who served under President George W Bush, told the U.S. television network Fox.
"If Israel's going to do anything against Bushehr it has to move in the next eight days. If they don't, then as I say, something Saddam Hussein wanted but couldn't get, a functioning nuclear reactor...the Iranians, sworn enemies of Israel, will have."
However, such concerns have been dismissed by nonproliferation experts.
Mark Fitzpatrick, a nonproliferation specialist at the Institute for Strategic Studies in London, described the Bushehr plant as a "sideshow," telling Reuters, "It shouldn't distract world attention from the real issue of enrichment."
Dalton says the views expressed by critics such as Bolton are "extreme" but acknowledges the Bushehr project contains elements of potential concern. That includes providing Iran with the opportunity to train more nuclear scientists and technicians who could then be reassigned for enrichment or other activities.
"Those who wish to restrict Iran's nuclear program to the absolute minimum, if it can't be eliminated entirely, see [the program] as a potential source of cadres who might at some stage be diverted to more nefarious uses of nuclear energy," Dalton says.
"And secondly, they see the possibility that Iran would take this unit out of safeguards and abrogate the agreements with Russia, thus in effect leaving the Nonproliferation Treaty. And then they might -- might -- be able to extract plutonium from the spent fuel rods and then, in turn, divert that for potentially military uses."