WASHINGTON: Confronted with a set of unattractive choices for dealing with an escalating nuclear threat from Iran, the Bush administration has adopted a policy of working through the United Nations and other international institutions to mobilize world opinion against the Islamic government in Tehran.

After disparaging the performance of the United Nations and its nuclear watchdog in dealing with Iraq, administration officials have gone out of their way to praise the work of the International Atomic Energy Agency on Iran. A senior State Department official described a report drawn up by the UN agency’s experts on Iranian nuclear capabilities as “factual” and “devastating,” adding that the Iranians have a “lot of explaining to do.”

US officials and independent experts have long suspected Iran of conducting a largely clandestine programme to produce the fissile material for a nuclear weapon through both plutonium separation and uranium enrichment. But public evidence of the scale and sophistication of the Iranian effort has emerged only over the last few weeks as the result of on-the-ground investigations by UN experts and Iranian government responses to allegations by exile groups.

The report submitted to the IAEA listed numerous anomalies in Iranian reporting of the handling of nuclear materials, including a 1991 shipment of natural uranium from China. More important, it demonstrated that Iran is developing a domestic capability for all stages of the nuclear fuel cycle, from the mining of uranium to the production of highly enriched uranium through centrifuge technology.

Exactly when Iran will be able to produce enough fissile material for a nuclear weapon is hotly debated both inside and outside the US government. Israeli Foreign Minister Silvan Shalom told the Russian newspaper Izvestia that Iran would possess a nuclear bomb “by the end of 2005 or early in 2006,” a prediction described as a worst-case scenario by independent experts.

US officials are more cautious than the Israelis, saying that the Iranians must resolve a number of complex technical problems before they can build a nuclear weapon. A senior State Department official said the “conservative” estimate of US intelligence agencies is that Iran could have nuclear weapons “toward the end” of the decade. Other officials argue that the Iranians will need significant foreign assistance to meet that target.

The Iranian nuclear programme began in 1957 under the Shah, with significant assistance from the United States, at a time when relations between Washington and Tehran were close. The programme was interrupted by the 1979 Islamic revolution, but resumed in the 1990s, with assistance from countries such as Russia, which agreed in 1995 to complete a 1,000-megawatt light water reactor at the Persian Gulf port of Bushehr for the production of electricity.

Iranian officials have long said that the nuclear programme is for civilian purposes only and that Iran would abide by the 1968 nuclear Non-Proliferation Treaty, which it ratified in 1970. US officials question why an oil-rich country would want to invest so much in nuclear power. They point out that Iran burns off considerably more energy in natural gas than it is ever likely to produce at Bushehr.

Under the terms of Iran’s agreement with Russia, Moscow will supply the fuel for the Bushehr reactor, beginning around 2005, and retrieve the spent fuel rods. US experts worry, however, that Iran could break out of the Non-Proliferation Treaty, renounce its international obligations and hang on to the fuel rods. Under that scenario, it could use the fuel rods to separate enough plutonium for more than 50 nuclear weapons.

A more likely route to an Iranian nuclear weapon, according to many experts, is uranium enrichment. In March, Iranian officials took IAEA experts to visit a centrifuge facility at Natanz, 200 miles south of Tehran, whose existence was first disclosed by an Iranian exile group, the Mujahideen-e-Khalq. The Iranians say that the centrifuges are designed to produce fuel for the Bushehr reactor, but Western experts fear that it could also produce enough highly enriched uranium for two or three nuclear bombs.

According to independent experts, the Bush administration’s focus on multilateral diplomacy as the preferred method for dealing with Iran reflects the paucity of other options. Administration officials have rejected the idea of negotiating limits to the Iranian nuclear programme as part of a grand diplomatic bargain with the country’s Islamic government, along the lines of the 1994 agreed framework with North Korea.

The fallback option is preemption along the lines of Israel’s 1981 attack on an Iraqi nuclear plant at Osirak. But the political, diplomatic and military obstacles to such an approach are much more formidable than those faced by the Israelis two decades ago, according to US officials and independent experts, and there is no guarantee of success.

“By disseminating their nuclear programme, the Iranians are making it bomb-proof,” said David Albright, president of the Institute for Science and International Security, a Washington- based think tank that tracks proliferation issues. “You would need extremely precise and good intelligence to make sure you got everything. The risk is that you would drive them out of the international structures that they are just beginning to engage in.”—Dawn/The LAT-WP News Service (c) The Washington Post.