Iran nuclear plans of "serious concern": U.N. body

VIENNA (Reuters) - The U.N. nuclear watchdog said on Friday Iran had failed to explain Western intelligence reports showing explosives and missile work linked to making atomic bombs and that this was a "serious concern".

The International Atomic Energy Agency (IAEA) said Iran had dismissed the intelligence as "baseless" or "fabricated" but had not provided acceptable answers.

It said Iran had provided increased cooperation on other issues in the past few months.

Iran's increased transparency amounted to a doubled-edged sword as it reaffirmed Tehran was forging ahead with uranium enrichment in defiance of U.N. Security Council demands to stop all proliferation-sensitive nuclear activity.

The IAEA findings, which also said Iran had failed to clear up all outstanding questions by an agreed February deadline, may spur the Security Council to adopt more sanctions as early as next week.

The United States, which has accused Iran of having a secret program to build nuclear weapons, said Tehran had failed to meet U.N. demands and that it would go on pressing for new sanctions against the Islamic Republic.

Senior diplomats from Britain, France, Germany, the United States, China and Russia would meet in Washington on Monday to discuss the next steps over Iran, Western officials said.

Iran, which says its nuclear program is only for power generation to meet the growing demands of its economy, hailed the IAEA's comments as a victory because it said the watchdog had found Tehran was pursuing peaceful activities.

In unusually strong wording, the IAEA said in a report Iran had not so far explained documentation pointing to undeclared efforts to "weaponize" nuclear materials by linking uranium processing with explosives and designing of a missile warhead.

Publishing details of the intelligence, the IAEA described tests on a 400-metre (1,300 ft) firing shaft seen as "relevant" to atomic arms research and a schematic layout of a missile cone "quite likely to be able to accommodate a nuclear device".

UNACCEPTABLE

IAEA officials said Iran's response to the intelligence reports was not acceptable and further talks would be pursued on the most worrisome remaining issue about past Iranian activity.

"The (intelligence) studies are a matter of serious concern and critical to an assessment of a possible military dimension to Iran's nuclear program," said the report issued by IAEA head Mohamed ElBaradei.

"The agency will not be in a position to make progress towards providing credible assurances about the absence of undeclared nuclear material and activities in Iran before reaching some clarity on the nature of the alleged studies."

One crucial requirement was for Iran to implement the IAEA's Additional Protocol, which allows snap inspections that could verify that Tehran is not engaged in secret bomb work beyond declared civilian atomic energy sites.

Without that there could be "no confidence in the exclusively peaceful nature of the program", said the IAEA.

"We are disappointed with Iran's continued failure to comply with its U.N. Security Council obligations and calls by the IAEA to suspend all proliferation-sensitive nuclear activities," said senior U.S. official Kate Starr.

"Until Iran meets its obligations the international community can have no confidence that Iran's nuclear program is peaceful," said Starr, a spokeswoman for the White House National Security Council.

But Iran, the world's fourth largest crude oil producer, said the IAEA report had reaffirmed its program was for peaceful purposes.

"I congratulate the Iranian nation for this success and victory which was a result of their resistance on (the country's) nuclear rights," chief nuclear negotiator Saeed Jalili said. "From our viewpoint this issue has ended."

Iran says it aims to refine uranium only to the low level needed for power plant fuel so it can export more oil wealth.

The IAEA said Iran had given its officials a long-sought look at work to launch a more durable centrifuge meant to overcome technical glitches hindering uranium enrichment.

It said Iran was testing "IR-2" centrifuges, an upgrade of a design obtained from Pakistani-led nuclear smugglers, in the pilot wing of its Natanz nuclear complex. IR-2s can enrich two or three times faster than P-1s.