* Iran enriches uranium to 20 percent at Fordow
* Site deep underground to protect against attacks
* Tehran says Israel, U.S. behind cyber attacks
* Israel minister: Any harm to Iran assets a “blessing” (Adds Iran commander, diplomats, IAEA, Israel, detail)
By Marcus George
DUBAI, Jan 28 (Reuters) - Iran has denied media reports of a major explosion at one of its most sensitive uranium enrichment sites, describing them as Western propaganda designed to influence upcoming nuclear negotiations.
Reuters has been unable to verify reports since Friday of an explosion early last week at the underground Fordow bunker, near the religious city of Qom, that some Israeli and Western media have said caused significant damage.
“The false news of an explosion at Fordow is Western propaganda ahead of nuclear negotiations to influence their process and outcome,” state news agency IRNA quoted the deputy head of Iran’s Atomic Energy Organisation, Saeed Shamseddin Bar Broudi, as saying late on Sunday.
Iran’s ISNA news agency quoted military commander Massoud Jazayeri as saying: “I deny an explosion at the Fordow site.”
In late 2011 the plant at Fordow began producing uranium enriched to 20 percent fissile purity, compared with the 3.5 percent level needed for nuclear energy plants. Several U.N. Security Council resolutions have ordered Iran to suspend all uranium enrichment.
Speculation of an explosion at Fordow followed an Iranian news agency report that global powers and Tehran could resume talks on Iran’s disputed nuclear programme on Monday and Tuesday. The European Union, the lead negotiator on the nuclear talks, said there was no such agreement.
Diplomats in Vienna, where the United Nations’ nuclear agency is based, said on Monday they had no knowledge of any incident at Fordow but were looking into the reports. One Western diplomat said he did not believe them to be correct.
The U.N. International Atomic Energy Agency (IAEA), which regularly inspects Iranian nuclear sites including Fordow, had no immediate comment.
Iran has accused Israel and the United States of trying to sabotage its nuclear programme, which the West suspects hides an attempt to develop atom bomb capability. The Islamic republic says its atomic programme is entirely peaceful.
Tehran has accused Israel and the United States of being behind cyber attacks on its nuclear programme and the assassination of its nuclear scientists.
Washington has denied any role in the killings, while Israel has declined to comment. No government has taken responsibility for the Stuxnet computer virus that destroyed centrifuges at Iran’s Natanz uranium enrichment facility in 2010, but it has been widely reported to have been a U.S.-Israeli project.
Israel, believed to be the Middle East’s only nuclear-armed state, has hinted at possible military action against Iran if sanctions and diplomacy fail to resolve the decade-old dispute.
Israeli Civil Defence Minister Avi Dichter told Israel’s Army Radio he could not say anything about the reported Fordow blast “beyond what I heard in the media.”
He added: “Any explosion in Iran which does not harm people but, rather, harms assets, is a blessing.”
Western governments say the higher-grade enrichment at Fordow is a significant step towards weapons-grade material, even though it is below the 90 percent level required for nuclear bombs.
The Islamic state says it is producing 20 percent uranium to make fuel for a research reactor in Tehran that produces medical isotopes.
Wrangling over dates and location have delayed resumption of talks between global powers and Iran, but Russian Foreign Minister Sergei Lavrov said on Monday both sides should “stop behaving like little children” and start work.
Three rounds of talks last year between Iran and the six powers - Russia, the United States, China, Britain, France and Germany - produced no breakthrough, increasing speculation Israel could attack Iranian nuclear installations. (Additional reporting by Fredrik Dahl in Vienna and Dan Williams in Jerusalem; Editing by Jon Boyle)