ALMATY, Kazakhstan - Iran and six world powers failed to reach agreement Saturday on how to reduce fears that Tehran might use its nuclear technology to make weapons, extending years of inconclusive talks and adding to concerns the diplomatic window on reaching a deal with Tehran may soon close.
Expectations that the negotiations were making progress rose as an afternoon session continued into the evening. But comments by the two sides after they ended made clear that they fell far short of making enough headway to qualify the meeting as a success.
"What matters in the end is substance, and … we are still a considerable distance apart," Catherine Ashton, the European Union's head of foreign policy, told reporters at the end of the two-day talks.
Ashton, the convener of the meeting, said negotiators would now consult with their capitals. She made no mention of plans for new talks - another sign that the gap dividing the two sides remains substantial. She said she would talk with chief Iranian negotiator Saeed Jalili by telephone over further steps.
Jalili spoke of "some distance between the positions of the two sides." He suggested Iran was ready to discuss meeting a key demand of the other side - cutting back its highest-grade uranium enrichment production and stockpile - but only if the six reciprocated with rewards far greater than they are now willing to give.
Western negotiators noted an improved atmosphere from previous sessions.
Still, the lack of forward movement in international negotiations that started a decade ago was certain to increase concerns that diplomacy was ineffective as a tool to stop Iran from moving toward nuclear-weapon making capacity.
"The Iranians are using the round of talks to pave the way toward a nuclear bomb," said Yuval Steinitz, the Israeli minister for intelligence and strategic affairs, in a text message to reporters. "Israel has already warned that the Iranians are taking advantage of the rounds of talks in order to buy time to advance in uranium enrichment, step by step, toward a nuclear weapon."
At the talks in the Kazakh city of Almaty, the U.S., Russia, China, Britain, France and Germany were asking Tehran to greatly limit its production and stockpiling of uranium enriched to 20 percent, which is just a technical step away from weapons-grade uranium.