MOSCOW, (Reuters) – Russia said yesterday it was  “very alarmed” by Iran’s failure to cooperate with the IAEA,  after the U.N. nuclear agency said it feared Tehran might be  working to develop a nuclear missile.

Supreme Leader Ayatollah Ali Khamenei repeated Iran’s  insistence that suspicions about its nuclear programme were  baseless. But the United States said the IAEA report lent weight  to its campaign for more sanctions against Tehran.

“We are very alarmed and we cannot accept this, that Iran is  refusing to cooperate with the IAEA,” Russian Foreign Minister  Sergei Lavrov told the radio station Ekho Moskvy.

“For about 20 years, the Iranian leadership carried out its  clandestine nuclear programme without reporting it to the IAEA,”  he said. “I do not understand why there was such secrecy.”

The IAEA on Thursday made public its concerns over a  classified analysis which concludes that Iran already has  explosives expertise relevant to a workable nuclear weapon.

“Some questions remain on the table and Iran has so far not  reacted to them,” Lavrov said. “We need to understand how  several documents concerning military nuclear technology found  their way to Iran.”

Russia — which wields a veto in the United Nations Security  Council — has in recent weeks raised suspicions publicly about  Iran’s nuclear activities, after for years saying it had no  evidence Tehran was seeking to build a nuclear bomb.

Foreign Ministry spokesman Andrei Nesterenko hinted that  talks on a sanctions resolution could start soon.

“No work is in progress at the U.N. Security Council in New  York today to prepare a possible sanctions-based resolution on  Iran … However, given the current circumstances, we cannot  fully rule out the possibility of starting this work.”

But Moscow reiterated its position that it will not block an  export of S-300 air defence missile systems to Iran, something  the United States and Israel say may help Iran protect its  nuclear facilities from any future air strikes.

“There is a contract to supply these systems to Iran, and we  will fulfil it,” Deputy Foreign Minister Sergei Ryabkov told  Interfax. “It is absolutely incorrect to put the emphasis on the  issue of S-300 supplies.”

Washington’s U.N. Ambassador Susan Rice said the IAEA report  “plainly underscores that Iran continues to flout its  international obligations”.

The nuclear watchdog’s comments showed “the urgency of  making the choice real to Iran that it could engage and uphold  its international obligations or, on the contrary, face  increased international pressure,” she told reporters.

Germany, one of the six powers negotiating with Iran on the  nuclear issue, added its voice to the pressure.

“The persistent defiance … of United Nations resolutions  and Tehran’s continuation of a dangerous nuclear policy are  forcing the international community to pursue further  comprehensive sanctions in New York against the regime in  Tehran,” government spokesman Ulrich Wilhelm said.

But he added: “We rule out a military solution.” The United  States says it wants a diplomatic solution but has not ruled out  military action.

German exporters called yesterday for tough sanctions, even  though Germany is among Iran’s biggest trading partners,  exporting more than 3.3 billion euros’ worth of goods in 2009.

Khamenei was quoted as saying by Iranian media: “The West’s  accusations are baseless because our religious beliefs bar us  from using such weapons … We do not believe in atomic weapons  and are not seeking that.”