LONDON, Sept. 6 (Xinhuanet) -- Iran is at least five years away from acquiring enough material for a nuclear weapon, a London-based think tank said on Tuesday.

    "If Iran threw caution to the wind, and sought a nuclear weaponcapability as quickly as possible without regard for internationalreaction, it might be able to produce enough highly enriched uranium for a single nuclear weapon by the end of this decade," said John Chipman, director of London's International Institute for Strategic Studies (IISS).

    At a press launch of the report titled "Iran's Strategic Weapons Programs -- A Net Assessment," Chipman said that unanticipated technical problems would lengthen the process.

    It was more likely that Iran would try to accumulate productioncapability over a longer period -- 10 to 15 years, said Gary Samore, editor of the report.

    The assessment report of Iran's strategic weapons program came just two weeks before the International Atomic Energy Agency (IAEA) will discuss whether to refer Iran to the UN Security Council, a move which could trigger sanctions on the Islamic country.

    "Our assessment is technical. The most interesting discussion is about political calculations and how Iran weighs the risks and benefits of acquiring nuclear weapons capability," Samore told reporters.

    Samore said the US would have a serious debate about military strikes if the Security Council failed to persuade Iran to freeze its program.

    "It will be important to apply international diplomacy in a waythat does not inspire Iran to abandon all restraint and seek a nuclear weapons capability," Chipman added.

    "Iran's nuclear option is not imminent...Rather than dash for abomb, Iran may seek gradually to acquire a much more substantial nuclear production capability over a decade or more before it decides whether to exercise a weapons option." said Chipman.

    Iran has been under international pressure since it resumed uranium conversion activities in the central city Isfahan on Aug. 8 and rejected the EU's comprehensive proposal to solve the issue.

    Tehran has repeatedly stressed that it will never give up its legal rights including uranium enrichment activities but will continue to cooperate with the international community.

    The US accuses Iran of developing nuclear weapons under the disguise of civil usage, a charge rejected by Tehran.

    On Sunday, Iran rejected an EU warning of referring its nuclearcase to the Security Council if Tehran did not stop sensitive nuclear activities. Enditem