A high-ranking Iranian delegation was supposed to meet International Atomic Energy Agency head Mohamed ElBaradei on Thursday to provide him with details of its plans to move closer to uranium enrichment, a process which can produce both fuel for nuclear energy or nuclear weapons.
Iranian representatives already rebuffed ElBaradei on Wednesday when he asked for clarification of their plans. But they said then they would be more forthcoming Thursday on what they describe as the resumption of research and development of uranium enrichment.
The European Union, with U.S. backing, then decided to give diplomacy another try in efforts to gain more international support for their stance.
Iran says it is interested in enrichment to make nuclear fuel, but the United States and an increasing number of other nations suspect Tehran wants the technology to make weapons-grade uranium for nuclear warheads.
Tehran says it will not actually begin enrichment Monday. But even the restarting of equipment testing would be viewed as the latest in a series of steps toward fully reviving the program in violation of Tehran's pledge for a full freeze on all of its aspects.
A diplomat close to the agency said that the Iranians appeared taken aback by the firmness of ElBaradei's demands Wednesday for more cooperation in his agency's probe of Tehran's nuclear activities. The diplomats who spoke to The Associated Press asked for anonymity because the meeting was private.
ElBaradei's demands and clear criticism of Iran's plans to move closer to enrichment was what apparently led the Iranians to not show for Thursday's meeting, the diplomat said.
Iran has come under heavy international pressure to abandon its program to produce fuel for its Russian-built nuclear reactor that is due to come online this year and for its future nuclear power plants.
But it has vowed never to give up the right to enrichment, which it says it has a right to under international law.