Still time for Iran nuclear fuel swap: think tank

VIENNA (Reuters) - A stalled plan for Iran to part with some of its nuclear material could yet succeed because Tehran still cannot make the reactor fuel it would get in return, a top Washington-based think tank said Thursday.

Major powers have cast doubt on a plan brokered by Brazil and Turkey for Iran to send abroad 1.2 tonnes of its low-enriched uranium (LEU), and pushed through a fourth round of U.N. sanctions against Tehran this month.

That offer resurrected parts of a deal brokered by the U.N. nuclear watchdog with three powers in October and which at the time would have divested Iran of 70 percent of its LEU, enough for a nuclear bomb if enriched to higher levels.

Western officials have questioned the value of doing the swap now, as Brazil and Turkey have suggested, because Iran has doubled its LEU stockpile and started higher enrichment, a further potential step toward weapons-grade uranium.

Despite these issues, the opportunity is still there, the Institute for Science and International Security (ISIS) said.

"There is still time for a low enriched uranium fuel swap deal, which would be in Iran's interest if it intends on fueling the Tehran Research Reactor (TRR) soon," it said in an online commentary. ISIS is one of the main Western think tanks tracking nuclear issues.

Iran has said the reactor, which makes isotopes used for cancer treatment, will run out of its Argentine-imported fuel stock at the end of the year.

As the talks to replenish this stock stalled, Tehran said it would make the fuel itself and said it started enriching uranium to higher levels in February for this purpose.

But ISIS said it cannot complete the plan soon because it lacks the technical ability. "Iran's inexperience in making fuel elements for the TRR raises questions about its claims that it needs to continue enriching up to 19.75 percent, especially given how soon Iran says it intends to produce fuel elements for the reactor," ISIS said.

Iran said Wednesday it had enriched 17 kg of uranium to this higher level, underscoring its determination to push ahead with its nuclear work.

It says the sanctions against it are illegal and that its atomic program is for peaceful uses only.

France, one of the few countries which could produce the reactor fuel now, has said Iran must stop enriching uranium to higher levels if a swap is to take place and address other concerns. The United States and Russia have also said this.

(Reporting by Sylvia Westall; editing by David Stamp)