U.S. Secretary of State John Kerry said "gaps" remain in high-stakes nuclear talks with Iran, despite "tangible progress," the Associated Press reports.
Kerry's Tuesday remark came days after he joined top diplomats from three other Western governments in Vienna, where negotiators are sprinting to reach a deal by Sunday on global fears about Iran's possible ability to construct nuclear bombs. Iran insists its atomic ambitions are peaceful, but Washington and its allies say Tehran must do more to assure other countries of that contention in order to win relief from international sanctions.
Iranian Foreign Minister Mohammad Javad Zarif on Monday said his country had proposed halting the expansion of its uranium-enrichment program for several years in exchange for the phased elimination of economic penalties, the New York Times reported. Tehran has called for any agreement to last between three to seven years, but Washington has pressed for a duration "in the double digits."
Kerry on Tuesday urged Iran to go further, by curbing its existing enrichment capacity, Reuters reported. The uranium-refinement process can generate fuel for civilian nuclear reactors, but it can also produce higher-grade material suited for weapons.
"We have made it crystal clear that the 19,000 [enrichment centrifuges] that are currently part of their program is too many," he said.
Zarif proposed converting the bulk of Iran's enriched uranium gas into an oxide powder that cannot readily be purified into bomb material, the Times reported. Under a potential deal, Tehran may also refrain from building a system to convert the oxide back into gaseous form.
Iran ultimately wants to produce its own nuclear power plant fuel. Zarif, though, said current fuel imports from Russia enable Tehran to bargain over how long any nuclear restrictions would last.
"Since our reactor doesn't need fuel for another seven years we don’t have to kill ourselves for it. We have time," the Iranian foreign minister said.