Iran has requested that it be permitted to continue conducting "research and development" with centrifuges, machines that can be used to develop material for nuclear weapons, diplomats said today.
"The Iranians asked to be allowed to continue conducting research and development with centrifuges during the freeze, but the Europeans told them no," a Western diplomat told Reuters news agency on condition of anonymity.
Iran promised the European Union last week it would suspend its entire uranium enrichment programme and all related activities in a bid to avoid a report to the UN Security Council for possible sanctions.
The suspension, which includes all work with centrifuges, took effect on Monday.
Centrifuges purify uranium to fuel power plants or weapons by spinning at supersonic speeds.
"Iran has asked to be allowed to test centrifuge rotors during the freeze," said a diplomat, who added that this would require permission to operate a number of centrifuges.
The Iranian delegation to the UN International Atomic Energy Agency (IAEA) was unavailable for comment. A diplomat close to the IAEA confirmed that Iran had made this request.