VIENNA, Nov 25: Iran has so far failed to meet a pledge to fully suspend uranium enrichment as it wants to use 20 centrifuge devices for research, UN atomic agency chief Mohamed ElBaradei said on Thursday , reporting a deadlock as his agency met on Tehran's alleged nuclear weapons program.

"We have completed our work with regard to verification of the suspension with regard to one exception and that's the request by Iran to exempt 20 centrifuges for R and D (research and development) without using nuclear materials," Mr ElBaradei told reporters.

In Tehran, Iranian President Mohammad Khatami criticized the European trio's draft as "not a good resolution", even as non-aligned states presented a softened version of the text for discussion in Vienna.

Iran's request goes against promises it made in an agreement with EU negotiators earlier this month to suspend uranium enrichment, the key step in making what can be fuel for nuclear reactors or in highly refined form the explosive core of atomic bombs, European diplomats said.

Centrifuges aligned in a series known as cascades spin at supersonic speeds to refine uranium into its enriched state. But Amir Hossein Zamani-Nia, the Iranian foreign ministry's international political affairs director, said in Vienna: "We have fulfilled our commitments under the Paris agreement." He did not elaborate.

A Western diplomat said it would be "outrageous" if Iran at the last minute exempted some centrifuges out of the some 1,000 it is believed to have, even if this is only for research purposes. "It is not acceptable to us," a European diplomat said, with the meeting continuing on Friday, and possibly into the weekend.

Iran was also taking a hardline stance against a draft UN resolution by Britain, France and Germany in moves which stalled a crucial IAEA meeting on allaying international concern over its nuclear program, which the United States claims is devoted to secretly developing atomic weapons.

EU REJECTION: Iran's demand to be allowed to use the centrifuges has been rejected by the European Union, which earlier this month negotiated a total uranium enrichment freeze in order to help Tehran avoid possible UN sanctions.