Speaking before the opening of talks in Paris with foreign ministers from the six countries who made the proposal, Rice said Iran's tepid response will force the powers to decide whether to take up the matter at the Security Council.
Rice said the five permanent members of the Security Council plus Germany could decide this evening whether to continue negotiations or turn to the UN Security Council.
Some countries, including the United States, fear Iran aims ultimately to develop nuclear weapons.
Earlier in the day, Finnish Foreign Minister Erkki Tuomioja warned Iran today that it faces UN Security Council action over its nuclear development program.
Tuomioja, whose country holds the European Union's rotating presidency, said that if Iran is not ready for cooperation the process will have to continue in the UN Security Council.
(compiled from agency reports)
A control panel at the Bushehr nuclear power plant (Fars)
CASCADES AND CENTRIFUGES: Experts and pundits alike continue to debate the goals and status of Iran's nuclear program. It remains unclear whether the program is, as Tehran insists, a purely peaceful enegy project or, as the United States claims, part of an effort to acquire nuclear weapons.
On June 7, 2006, RFE/RL correspondent Charles Recknagel spoke with nuclear expert Shannon Kile of the Stockholm International Peace Research Institute in Sweden to help sort through some of the technical issues involved. "[Natanz] will be quite a large plant," Kile said. "There will be about 50,000 centrifuges and how much enriched uranium that can produce [is] hard to say because the efficiency of the centrifuges is not really known yet. But it would clearly be enough to be able to produce enough [highly-enriched uranium] for a nuclear weapon in fairly short order, if that's the route that they chose to go...." (more)