GENEVA — Iran is expected to make an offer Tuesday to scale back its effort to enrich uranium, a move that a year ago would have been a significant concession to the West. But Iran’s nuclear abilities have advanced so far since then that specialists say it will take far more than that to assure the West that Tehran does not have the capacity to quickly produce a nuclear weapon.
With thousands of advanced centrifuges spinning and Iranian engineers working on a plant that will produce plutonium — which also can be used in a weapon — Iran’s program presents a daunting challenge for negotiators determined to roll back its nuclear activities.
Both sides enter the nuclear talks that begin here Tuesday with inherent strengths and weaknesses.
Iran walks in with a nuclear program that cannot easily be turned back, while the West has imposed economic sanctions that have crippled the Iranian economy.
And if Iran is going to maintain the right to enrich uranium to even low levels, as it continues to insists it must, the West would surely demand highly intrusive inspections — far more than Iran has tolerated in the past. How these matters are resolved will go far in deciding the success or failure of the talks.
In 2003, Iran had a handful of relatively unsophisticated centrifuges. Today, it has at least 19,000, and 1,000 of those are highly advanced. Those have been installed but are not being used to enrich uranium
That is more than enough, specialists say, to transform low-enriched uranium from the 3 percent to 5 percent range to 20 percent — near weapons grade — in a few months.
“Ending production of 20 percent enriched uranium is not sufficient to prevent breakout, because Iran can produce nuclear weapons using low-enriched uranium and a large number of centrifuge machines,” said Gary Samore, a senior aide on nonproliferation on the National Security Council in President Obama’s first term.
In addition, Tehran is nearing completion of a heavy-water reactor that would be capable of producing plutonium for nuclear bombs.
The talks in Geneva are the first between Iran and the United States and five other world powers since the election of Iran’s new president, Hassan Rouhani, who took office in August and has made a priority of easing the crippling sanctions imposed on Iran over its nuclear activities.
A series of conciliatory messages and speeches from Rouhani and other Iranian officials — capped by a phone call to the Iranian president from Obama — has helped foster the most promising atmosphere for negotiations since 2003.
A senior American official said Monday the United States was heartened by the change of tone in Tehran and believed Rouhani’s election signals a sincere intention to chart “a more moderate course.”
But the official also said that the United States and its partners were still waiting to see if Iran would take concrete steps to constrain the pace and scope of its nuclear program.