But it could buy some time for the international community to evaluate the nuclear program and to negotiate safeguards aimed at preventing Iran from building a nuclear bomb, nuclear and diplomatic experts say.
Then again it could also be, as some critics of President Obama's diplomatic overtures to Tehran insist, a way for the Iranian regime to stave off tough international sanctions or even military strikes against nuclear facilities.
Earlier this month, Iran initially accepted the idea of sending as much as three-quarters of its low-enriched uranium stockpile out of the country. The material would be further refined to a higher-enriched form that's needed for a Tehran research reactor. But in the run-up to Monday's meeting with American, French, and Russian officials, Iran sent mixed signals. Then, by the end of the meeting, the head of the International Atomic Energy Agency, Mohamed ElBaradei, said the discussions were a "good start" and would continue Tuesday.
That's enough for some Western officials to hold out hope that the uranium swap deal – coupled with international inspections of a recently revealed nuclear facility – could open the way to a plan for halting Iran's nuclear ambitions.
With this plan, "we are buying something like seven to 10 months," says a senior European diplomat in Washington with close knowledge of the nuclear talks. "Perhaps step by step, we could build something out of this."
Iran is known to have about 1,800 kilograms (or about 4,000 pounds) of low-enriched uranium. An agreement to ship as much as three-quarters of that out of the country – to be refined in Russia and turned into fuel rods in France – would put Iran below the threshold of low-enriched uranium needed to begin the process of developing highly enriched fuel for a nuclear weapon.
If the centrifuges that Iran has continue to spin, however, without additional internationally imposed limitations and safeguards, the country could rebuild its low-enriched uranium stockpile to current levels by sometime next year. "And we'd be back to Square 1," adds the European diplomat, who spoke on condition of anonymity.
For the Obama administration, Iran's response to the fuel deal is one test of how far talks can go toward the goal of stopping Iran from building a nuclear weapon. Another test will be Tehran's response to inspections, set for next week, at a secret nuclear facility near the holy city of Qom that was disclosed last month.
Both tests will suggest Iran's willingness to accept permanent and verifiable limits on its nuclear program.
Gary Sick, a security expert on Tehran who has advised the Obama administration, calls the fuel swap plan "a step forward." Speaking recently in a conference call organized by the Israel Policy Forum, he said, "If they renege on this, if they back away from it, then we find out what they really mean to do."
At the same time, the plan can be considered only "the beginning of the beginning" of difficult negotiations with Iran, Mr. Sick says. "It's nowhere near an agreement that we could rely on for verification," he said.
Yet it remains to be seen whether this initial plan could even be negotiated in time to suit all the involved parties. For once, some Europeans involved in the international negotiations with Tehran – most notably the French – are sounding more pressed than the US to determine soon if the talks can succeed or if tougher economic sanctions should be sought.
"The two important issues here are the volume" of low-enriched uranium that Iran would agree to send out of the country, and "the timing," says the European diplomat. "We want this done before the end of the year."
Iran's nuclear disclosures: why they matter
A secret nuclear site. "Project 110." Offers to ship fuel abroad. Part of Iran's quest to be regional power? Click here to read more.
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